Download Indicators of syntactic complexity in adults with - UvA-DARE

Indicators of syntactic complexity in adults with
congenital moderate-to-severe hearing loss
Nienke Stolk
Student number: 0308498
August 2012
The Faculty of Humanities
MA thesis, General Linguistics (20 ECTS)
supervisor UvA: dr. J. de Jong
assessor UvA: prof. dr. A.E. Baker
supervisors VUmc: drs. E. Huysmans en dr. S.T. Goverts
Abstract
Purpose: In this thesis the syntactic complexity of the spontaneous speech of Dutch
normal hearing (NH) and moderate-to-severe congenital hearing impaired (MSCHI)
adults was studied. The aim of the study was to examine the differences in syntactic
complexity in spontaneous speech in both groups, NH and MSCHI, using nominal,
adverbial and relative subordinate clauses, and more specifically the clausal densities
(average number of clauses per T-unit), as an indicator for syntactic complexity.
Method: The spontaneous speech of 20 MSCHI and 10 NH adults was collected using
a “favourite games or sport”- task (FGST) to elicit expository discourse. All samples
were audio taped, transcribed and analysed, measuring syntactic complexity of
speech by using MLU, MLU5L, clausal densities, % subordination type as measures
for syntactic complexity. Errors and avoidance strategies were analyzed and ad hoc
categorized. Compared to normal hearing adults syntactically less complex language,
the uses of compensatory strategies to avoid complexity and more morpho-syntactic
errors were expected to be observed in moderate-to-severe hearing impaired
participants.
Results: No significant differences were found on the complexity variables between
NH and MSCHI adults in spontaneous speech. On average both MSCHI and NH
produced an equal number of subordinate clauses, the same applied for the different
types of subordination. However, interesting differences were found on the error
rates between MSCHI and NH. MSCHI made significantly more morpho-syntactic
errors within the subordinate clauses (including errors made both inside and outside
the subordinate structure) than NH adults did. Only few example of avoidance
strategies were found in the speech sample.
Conclusion: Based on the outcomes of this study there seem to be no differences in
the syntactic complexity in the spontaneous speech of MSCHI and NH adults.
Possible explanations might lie in the experimental group, due to the limited size of
the research and higher educational level of the MSCHI adults. Where static analysis
could be applied it demonstrated no significant group differences.
KEY WORDS: syntactic complexity, subordination, hearing impairment, adults,
spontaneous speech, clausal density
2
Preface
This Master's thesis forms the last part of the Master program General
Linguistics of the Faculty of Humanities at the University of Amsterdam. The present
investigation is part of an exploratory study on the effect of congenital hearing
impairment on language performance in (young) adults, that is currently being
conducted by Elke Huysmans at the VU medical centre, department KNO–audiology.
The aim of that project is to obtain a differentiated description of the moderate-tosevere congenital hearing impaired (MSCHI) induced language deficits, which persist
through (young) adulthood. In this thesis I studied the syntactic complexity of the
spontaneous speech of Dutch normal hearing (NH) and moderate-to-severe
congenital hearing impaired (MSCHI) adults. With this investigation I want to
contribute to the limited scientific research on the characteristics of language and
language problems that occur in adults. By providing insight in the problems that
remain in hearing impaired adults’ production speech, I hope to contribute to the
practical field of speech therapist who help hearing impaired children acquiring a full
command of language.
Special thanks goes to Elke Huysmans, my supervisor from the VU medical
centre for inspiring me with the own PhD research on hearing impaired and giving
me the opportunity to conduct research in an adjacent area within her project. Her
knowledge in the field of hearing impairment and linguistics, and knowledge in the
field of hearing and hearing impairment and methodological knowledge of Theo
Goverts whom I also want to thank sincerely, were of great value and contributed to
the creation of this thesis. Also thanks are due to my supervisor, dr. Jan de Jong, for
his ideas, time and frequent help to get me back on track. Thanks also to the second
reader, prof. dr. Anne E. Baker.
Finally, I would like to thank my family and friends for their support during my
study. For questions or remarks as a result of this thesis an email can be sent to:
[email protected]
Nienke Stolk, Amsterdam, August 2012
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Table of Contents
Page
Introduction ............................................................................................................... 6
1
Language development of congenital sensorineural hearing impaired people .. 8
1.1
Congenital sensory neural hearing loss .................................................................. 8
1.2
Language acquisition with a moderate or severe hearing impairment ........................ 10
1.2.1 Language acquisition and linguistic performance in hearing impaired children ............. 12
1.2.2 Language performance in hearing impaired adolescents (and adults) ........................ 15
1.3
Summary and discussion .................................................................................... 19
2.
Syntactic complexity ...................................................................................... 20
2.1
Acquisition of syntactic complexity ....................................................................... 20
2.2
Subordination ................................................................................................... 24
2.3
Measuring syntactic complexity ........................................................................... 26
2.3.1 Mean Length of Utterance ................................................................................... 26
2.3.2 Clausal densities ............................................................................................... 27
2.4
Research questions ........................................................................................... 28
2.5
Summary and discussion .................................................................................... 31
3
Method ............................................................................................................ 32
3.1
Participants ...................................................................................................... 32
3.2
Data collection .................................................................................................. 34
3.3
Analysis ........................................................................................................... 36
3.3.1 Syntactic complexity ......................................................................................... 37
3.3.2 Errors ............................................................................................................. 39
3.3.3
Avoidance of syntactic complexity and compensatory strategies ............................. 41
4.
Results ............................................................................................................ 43
4
4.1
Results for syntactic complexity .......................................................................... 44
4.2
Results for error analysis .................................................................................... 46
4.3
Results for avoidance strategies .......................................................................... 48
5.
Conclusion and discussion ............................................................................. 49
6.
Bibliography .................................................................................................. 52
Appendix I: List of abbreviations used in this thesis and appendix II ................................ 59
Appendix II: Detailed information about the discussed studies......................................... 60
Appendix III: Research data ...................................................................................... 64
5
Introduction
The present investigation is part of an exploratory study of the effect of
congenital hearing impairment on language performance in (young) adults. In this
thesis the syntactic complexity of the spontaneous speech Dutch moderate-to-severe
congenital hearing impaired (MSCHI) adults is studied and compared to Dutch adults
with normal hearing (NH). The thesis contains a literature review on research
conducted on language development in congenital hearing impaired and the
acquisition of syntactic complexity. It also contains an empirical part in which
different types of subordinate clauses as they occur in spontaneous speech of normal
hearing and moderate-to-severe congenital hearing impaired adults will be
investigated. Different types of subordinate clauses are taken as an indicator for the
syntactic complexity in spoken language.
The language intake of hearing impaired individuals is partial and degraded which
provides inadequate information, and gives the child an insufficient model of the
language that has to be learned to (Delage and Tuller 2007). Davis et al. (1986)
found that even minimal hearing loss places children at risk for language and
learning problems, with regard to language production and language processing.
Delage and Tuller (2007) examined the effect of hearing loss on language
performance in adolescents finding that language does not normalize with age.
Consequences of hearing loss on the language development in children and the
acquisition of full language competence will be discussed in the first chapter of this
thesis.
Language impairment has been reported for children with hearing loss in the
areas of phonology, vocabulary and morphology and syntax (Elfenbein et al., 1994;
Moeller et al. 2007; McGuckian and Henry 2007). Several studies have explored the
acquisition of syntax and syntactic complexity in children with hearing loss, but
relatively few studies (Delage and Tuller 2007; Nippold et al. 2005; Nippold et al.
2008; Nippold, 2009) have examined the same linguistic aspects in hearing impaired
adolescents and adults. These studies have given new insights on the importance of
syntactic complexity as an indicator for the severity of the language impairment.
Nieminen wrote: “Growth in complexity is perceived as an index of development in
linguistic abilities and therefore, complexity is an essential concept in language
acquisition studies” (Nieminen, 2009 p.173). A description of syntactic complexity
and the development of syntax is necessary in order to understand the hierarchy of
6
syntactic complexity. Chapter 2 will give an overview of the most important, recent
studies on syntactic complexity in hearing impaired children, adolescents and adults
(Delage and Tuller 2007; Nippold et al. 2005; Nippold et al. 2008; Nippold, 2009).
These studies will serve as a framework for the research done for this thesis, which
will examine the differences in syntactic complexity in both groups, normal hearing
and moderate-to-severe hearing impaired, using nominal, adverbial and relative
subordinate clauses, and more specifically the clausal densities (average number of a
clause type per T-unit), as an indicator of syntactic complexity. Based on the
previous research of Nippold and Delage et al. research questions and hypotheses
will be formulated about the syntactic complexity of spontaneous speech of hearing
impaired adults (chapter 2.5), that will form the core of the empirical research.
For the exploratory part of this thesis the spontaneous speech of normal hearing
adults (N=10) and moderate-to-severe hearing impaired adults (N=20), elicited in
expository discourse to challenge subjects to use as complex language as possible, is
analyzed for syntactic complexity. The methodology and variables are described in
chapter 3. To provide answers to the research questions addressed in this thesis a
comparison between normal hearing and moderate-to-severe hearing impaired
adults will be made on the complexity variables. These findings will provide results
on the potential variance between the syntactic complexity for both groups. Results
of this research will be presented in chapter 4 and this thesis will be concluded in
chapter 5 with a discussion on the research as well as recommendations for future
research.
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1
Language development of congenital sensorineural hearing impaired
people
1.1
Congenital sensory neural hearing loss
Hearing is the ability to perceive vibrations in the air, captured by the ear drum
in the outer ear, transmitted by the middle ear through the auditory bones into the
basilar membrane in the inner ear, where the vibrations in the cochlea are converted
into an electric discharge by the auditory nerve. These oscillations, sound waves, can
vary in amplitude, frequency and phase, making a difference in the perception of
sounds. This sensitivity to sound is not the same for everyone. On average, people
are able to perceive sounds between 20 Hz and 20 KHz, the frequency of sound. The
amplitude of the sound should be louder than the so-called hearing threshold for
people to be able to perceive them. This threshold is displayed in decibels and differs
per individual. The hearing threshold for normal hearing people is between 0- 20 dB.
(Audiologieboek.nl (2009), chapter 2)
Figure 1. The anatomy of the ear seen from a cross-sectional view (www.phonak.com)
As shown in the picture above sound perception is a complex process, which
requires that the outer, middle and inner ear are working properly. A problem in any
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part of the ear can cause hearing problems; either a hearing disorder or hearing
loss, that often accompany each other.
There are two main forms of hearing loss that can be distinguished depending on
which part of the ear is affected. The first form is sensory neural hearing loss, an
inner ear problem, which means that sounds are not efficiently transmitted by the
auditory nerve into the brain. The other form of hearing loss is conductive hearing
loss, occurring because of a mechanical problem in the outer or middle ear, which is
a result of some kind of obstruction in the system or amplifier that regulates the
sound. Hearing loss can also be divided into congenital hearing loss meaning that the
hearing loss is innate, and acquired hearing loss, appearing after birth, which is
usually the result of aging. (Audiologieboek.nl (2009) chapter 1)
The severity of hearing loss is expressed in decibels (dB), and is determined by
measuring the hearing thresholds for different frequencies (250, 500, 1000, 2000
and 4000 Hz). The average hearing loss is calculated by taking the average value of
the three most sensitive frequencies in the vocal area, the so-called Fletcher Index
(FlI). The frequencies are 500, 1000 and 2000 Hz. The degree of hearing loss is,
based on the number of decibels of hearing loss, overall classified into several
categories, ranging from normal (0 dB) hearing to deafness. The overview below
shows one of the more commonly used classification systems (Clark, 1981).
-10 to 15 dB loss in the better ear
= normal hearing
16 to 25 dB loss in the better ear
= slight hearing loss
26 to 40 dB loss in the better ear
= mild hearing loss
41 to 55 dB loss in the better ear
= moderate hearing loss
56 to 70 dB loss in the better ear
= moderately severe hearing loss
71 to 90 dB loss in the better ear
= severe hearing loss
more than 90 dB loss in the better ear
= profound hearing loss
Several researchers report that the degree of hearing loss is an important factor
for language development of children with hearing problems (Bamford and Saunders
1999; Bench and Bamford 1979; Mogford 1993). Davis et al (1986) found that even
minimal hearing loss places children at risk for language and learning problems, with
regard to both the area of language production and the area of language processing.
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1.2
Language acquisition with a moderate or severe hearing impairment
This study focuses on the characteristics and the differences in syntactic
complexity in oral language between hearing-impaired and normal hearing adults.
Hearing loss is an important factor for language development (Bamford and
Saunders 1999) and a risk for language and learning problems (Davis et al. 1986).
Although in this thesis the focus is on hearing-impaired adults, it is very interesting
to look at the language development of hearing impaired children. A logical
assumption is that characteristics of (atypical) adult language production arise as a
result of (atypical) language development. Do congenital hearing impaired children
go through different or delayed language development compared to normal hearing
peers as a result of their hearing loss? Which language areas are affected and in
which areas problems will remain later in life? Results from studies of language
development in hearing impaired children may explain if and why there are problems
in certain language areas that may persist during adolescence and into adulthood.
Therefore a review of studies on language development in mild-to-severe hearing
impaired children and language of mild-to-severe hearing impaired adolescents and
adults will be the subject of the following sections (respectively 1.2.1 and 1.2.2).
However, firstly some general issues will be addressed.
Young language learning children acquire language and speech by auditory
environmental language input. Normal language learning occurs only when a child is
exposed to language early in life. Children, regardless of language education,
develop a vocabulary and learn to abstract the underlying structures and patterns
that are inherent to their mother tongue from the auditory input, combining this
pattern detection with their computational abilities and specific social (pragmatic)
skills (Delage et al., 2008). Exposure beginning later in life, or absence or partial
absence of early exposure to spoken language “may lead to life-long changes in the
ability to learn language” (Kuhl 2004, p.831).
Researchers suggest that natural language acquisition that is based solely on
language input, unlike learning a second language through language input and
language education, can only take place during ‘the’ critical period. The critical period
hypothesis claims that the first years of life, the period from early-to-mid childhood
(age 5 to puberty), is the ideal period for a child to acquire a first language in a
linguistically rich environment (Lenneberg et al. 1967). In language development,
“the effects over age of first exposure are approximately linear through childhood
with a flattening of the function in adulthood” (Newport 1990, 20). These findings
argue that maturational language-particular constraints, ensuring successful
10
language learning, exist early in life and are weaker with increasing maturation
(Newport 1990). If the child is not exposed to auditory input or the stimuli are not
adequate during the critical period, it will never achieve a full command of language.
Based on this assumption it is clear that for good language development it is
extremely important that during this critical period the language-learning child can
fully benefit from the auditory language input. Thus, good hearing and an efficient
way of processing auditory language input are essential for language development.
This is a crucial point, which explains why in children with innate hearing loss
problems in language acquisition (could) arise, problems that could persist in
adolescents and adults.
Kumaravadivelu (1994) describes the problem hearing impaired children are
facing by making an important distinction between language input and language
intake defining language input as the language that is directed or spoken in the
environment of the child, whilst intake is what the child has processed/perceived
from the input. Even if the environment is linguistically rich, children who are hard of
hearing from birth, as previously described, have a language intake that is partial
and distorted. This means that they have to learn a language during the critical
period based on a poor(er) language intake. They cannot fully benefit from the
auditory input due to their congenital hearing loss, unlike normal hearing children.
The language-impaired child will be hampered by the hearing impairment, but also
by the distorted acoustic signal, even if it is wearing hearing aids. The acoustic
information is insufficient with respect to the language to be learned. This means
that many children with mild-to-severe hearing loss are at risk for delayed language
development (Davis et al., 1986; Mogford 1993; Bamford and Saunders 1999).
Even after receiving hearing aids or cochlear implants a mildly, moderately or
severely hearing impaired child tends to delay in spoken language. Several studies
concerning language development in deaf and hard of hearing children show that
there is large individual variation, but even the children with high language scores
are behind normal hearing children when it comes to (spoken) language
development (Norbury, et al.,2001; Elfenbein et al., 1994; Moeller 2007; Spencer
and Marschalk, 2006; Svirsky et al., 2000). Research has shown that the severity of
the hearing impairment in children is weak or even not related to scores on linguistic
tasks (nor the age of detection) (Blamey et al., 2001, Norbury et al., 2001, and
Gilbertson & Kamhi, 1995; Tuller & Jakubowicz, 2004; Friedmann & Szterman,
2006). The large individual differences thus cannot be attributed solely to the
severity of the hearing loss (whether or not compensated by hearing devices), but
also reflect differences in acquisition rate, maturational and environmental factors.
11
The same individual variation occurs in typical developing children, although their
overall level of linguistic development is generally higher than for hearing impaired
children. These individual differences continue along the critical period during
adolescence and into adulthood (Nippold et al., 2005).
1.2.1 Language acquisition and linguistic performance in hearing impaired
children
Much research has been done on language acquisition and performance of
children with severe to profound hearing loss, and less on mild-to-moderate (MMLH)
and moderate-to-severe hearing loss (MSHL). Language impairment has been
reported for children with hearing loss in the areas of phonology, vocabulary,
morphology and syntax. Moeller et al (2007) give an overview of the research
regarding the development of language and literacy in children with mild-to-severe
hearing impairment. Because of language development in hearing impaired children
is much more studied than the language of adolescents and adults it is a great
source of information about the characteristics of language impairment that also
could go for adolescents and adults. Cross-sectional on language acquisition in
hearing impaired children can lead to predictions about the language of hearing
impaired adults. In this review the focus will be on the acquisition of spoken
language and language domains that are acquired later in language development
and cause problems that even remain clearly visible after the critical period into
adolescence and adulthood.
From birth the language intake of the hearing impaired child is partial and
distorted from the input they get from their environment. Their quality and the
extent of their auditory-linguistic experience differ from normal hearing children
(Moeller, 2007). Hearing impaired children are in different ways hampered by their
diminished hearing. Because of their hearing loss, hearing impaired children miss
certain sounds and syllables or perceive them distorted. The child imitates the
language it perceives. The hearing, however, gives inadequate information about
word forms and morphemes, and also insufficient information to adjust its own
speech. This affects hearing impaired children’s phonological awareness, and cause
problems with language production but also with language comprehension (Calvert,
1982).
Hearing impaired children show poor productive (and receptive) vocabulary skills,
and they slowly expand their vocabulary. From research on new word learning and
12
semantic development it can be concluded that word learning delay in mild-tomoderate hearing impaired children is highly related to difficulties in coding, storing
and retrieving phonological information (Gilbertson & Kamhi, 1995; Norbury et al.,
2001). The rate at which mild-to-moderate hearing impaired children learn new
words is not linked to the severity of hearing loss, but is related to their phonological
processing skills and phonological memory (Gilbertson & Kamhi, 1995). These
phonological processing problems are to some extent related to the degree of
hearing loss. Word repetition was observed to be directly related to the degree of
average pure tone loss, no such relationship was found between novel word learning
and degree of hearing loss (Briscoe et al., 2001). The effects of hearing impairment
on phonological and vocabulary development are also seen in the development of
morphology and syntax.
Language learning children acquire their mother tongue by abstracting the
morpho-syntactic rules from the language input they get. Because hearing impaired
children do not perceive these often unstressed, but very important morphemes from
their language input, as well as normal hearing children, hearing impaired children
can have more difficulties to determine the morpho-syntactic rules of the language
offered to them. Unstressed syllables or bound morphemes, often grammatical
elements that mark rules like verb morphology (tense, agreement) and plural forms
are difficult for hearing impaired children to observe and are serious obstacles to
their development of morpho-syntax. This could lead to problems with language
comprehension, but it also would have consequences for their language production
(Elfenbein et al., 1994). These elements are indispensable for the acquisition (and
production) of complex syntax.
In most young children syntax emerges around the age of 16 months, when the
first multi-word sentences are produced (Gillis en Schaerlaekens, 2000). In this first
stage of syntactic language development, children form (mainly two word) sentences
using the so-called build-up and break-down systems, with which they try their
syntactic abilities (Gilles en Schaerlaekens, 2000 p. 22). This means that children
extend their sentences by using separate words (or phrases) in varying
combinations, resulting in primitive utterances that resemble telegraphic. This
telegraphic phase is a multi-word phase, which is characterized by short sentences,
which contain little or no function words, and do not have morphology. From this
stage on, sentences refine and expand, which means they will consist of more words
(nouns, verbs, determiners, conjunctions etc.) with appropriate morphology and
within increasingly complex syntactic structures. This means that the early stages of
language development are characterized by the appearance of new structures while
13
language in later life is characterized by the appearance of combinations of different
syntactic structures that were acquired at a younger age, now resulting in complex
syntax (Gillis en Schaerlaekens, 2000).
For many young children the acquisition of complex (morpho-)syntax appears to
be effortless (Marinellie, 2004), but it is clear that as a result of their hearing loss,
hearing impaired children are at increased risk, compared to normal hearing
children, for having delay in the acquisition and problems in use of (complex)
morpho-syntax. Studies on morpho-syntactic development in children with hearing
impairment (especially mild-to-moderate hearing impaired) are relatively recent and
research findings in this area are varied. Bol and Kuiken (1988) investigated the
spontaneous language production of a group of Dutch children (age 3;0-9;0) with
moderate-to-severe hearing loss. On the morphological level, there was a low
production of articles, function words, pronouns, copula, and auxiliary verbs. The
children made many errors in verb inflection, especially in the present singular and
past simple. Plural morphology in nouns was at the same level as their hearing
peers. These results can be compared to those of Bamford and Bench (1979) in their
study of English-speaking children. Norbury et al. (2001) found that English mild-tomoderate hearing impaired children do not have more difficulty than normal hearing
children with verb conjugations (tense and/ or agreement), although a subset of
hearing impaired children showed problems with past tense (for example regular
walk/ walked and irregular give/gave) and singular –s (he drink(ø) lemonade). These
results (Bamford and Bench, 1979; Bol and Kuiken, 1988; Norbury et al., 2001)
suggest that mild-to-severe hearing impaired children may have problems mastering
verb morphology.
McGuckian & Henry (2007), studying the production accuracy of grammatical
morphemes (GM) in spontaneous language production of children with mild-tomoderate hearing loss, found significant differences in grammatical morpheme
production between a mild-to-moderate hearing impaired and a normal hearing Mean
Length of Utterance (MLU)-matched control group. Not only is there a delayed
morphological development in mild-to-moderate hearing impaired children, but the
application of the morphological rules is also less accurate. The order of grammatical
morpheme accuracy for the mild-to-moderate hearing impaired group was
characteristic of that reported for second language learners of English. Findings of
Elfenbein et al. (1994) suggested that the frequency of grammatical errors was
related to the degree of hearing loss. Overall patterns of development they observed
in 40 mild-to-moderate hearing impaired children seemed to be similar to typically
developing children but the hearing impaired children were, whether or not seriously,
14
behind. Error rates were higher for moderate-to-severe congenital hearing impaired
children than in typically developing children, with most errors (most of them
omissions) made in complex syntax, verb structures, bound morphemes and
pronouns. In Dutch moderate-to-severe hearing impaired children Bol and Kuiken
(1988) found a lower Mean Length of Utterance for hearing impaired children than
for their normal hearing peers. Bol and Kuiken observed a delay for morphosyntactic structures that increased as it came to structures from later acquisition
stages. Moderate-to-severe hearing impaired children continued to (over)produce
syntactic structures from earlier developmental stage and produced significantly less
complex structures; e.g. structures containing more than 4 phrases, and
coordination.
1.2.2 Language performance in hearing impaired adolescents (and adults)
Recent research has examined the same linguistic aspects as described in section
1.2.1, but than in hearing impaired adolescents and adults (Delage 2007; Hamann et
al. 2007; Delage & Tuller 2009; Tuller et al. 2012). The limited number of
investigations done into the lasting effects of hearing impairment in older people
show that the language areas affected in younger children to a greater or lesser
extent also create problems for adolescents and adults. These studies have provided
four main new insights and will be discussed below.
The first important finding was observed by Delage and Tuller (2007), who
examined the effect of hearing loss on language performance in adolescents (N=19,
age 11-15) with mild-to-moderate (21 to 70 dB) hearing loss, questioning if
language (generally or in certain areas) normalizes with age. In normal hearing
people in the area of phonology and morpho-syntax, most linguistic skills are
acquired by the age of 12 (Lenneberg et al., 1967). The results of Delage and Tuller
(2007) research showed that more than half of the adolescents with mild-tomoderate hearing loss participating in this study had particular difficulties in
phonology and morpho-syntax. The scores of mild-to-moderate impaired participants
were significantly lower than those of typically developing controls on grammatical
judgement, expressive grammar (French clitics) and phonology. Scores in these
areas were highly correlated. Oral comprehension, written language and vocabulary
seemed to be relatively unaffected. Language impairment in morpho-syntax and
phonology was related to severity of hearing loss in this study (p<.05). No
correlation could be established between age and hearing loss detection or age of
15
hearing aid fitting and language performance. No significant correlation was found
between language scores and age or for language scores and nonverbal intelligence.
The latter suggests that it does not seem to be the case that intersubject variation
could be explained by something like general intelligence. Delage and Tuller (2007)
concluded that language impairment thus is not resolved in hearing impaired
adolescents and that there is no normalization with age.
Indeed, while a negative effect of hearing loss was observed in children, but
correlation for the severity of their hearing loss on their language performance was
not observed, correlation between average hearing loss and performance in morphosyntax and phonology was found for adolescents. Delage and Tuller (2007, p.1300)
concluded that this effect, only found after childhood “might be because linguistic
development is basically complete after adolescence”) and the fact that this tendency
was not observed in children can be declared by the “developmental rhythms that
vary from child to child”. Although the effects of hearing loss in children are visible, it
is difficult to link language problems to the severity of hearing loss and to predict to
what extent these problems persist at the end stage of language acquisition. In
adolescents and adults, the effect of the end of the critical period is visible. The main
and lasting effects of hearing loss can clearly be identified, because they have
reached the (almost) final stage of language development. This makes (young)
adults an interesting research group to study, because it may reveal and give clearer
insights in persistent language problems arising early in language development and
remaining after the critical period into adolescence and beyond.
Secondly, consistent with the observation of language not normalizing with
age, the studies of Delage and Tuller (2007 and 2009) and Delage et al. (2008)
seem to show that the remaining problems in mild-to-moderate hearing impaired
adults persist particularly in morpho-syntax, and seem to lie mostly in the last
acquired most complex structures of language. Similar results were found for
adolescents with specific language impairment (see Tuller, et. al 2012; Hamann,
2007; Marinellie, 2004). Delage et al. (2008) studied morpho-syntax in French
adolescents, focussing on relative clause acquisition in atypical acquisition of French.
They argued that, apart from movement, other factors such as distance, but
moreover depth of embedding play a role for complexity. Children and adolescents
start with shorter movement, producing subject relatives and so-called pseudorelatives, which are relative constructions that involve lees deeply embedding
clauses. They avoid movement (non-subject relatives) and computations which
involve deeper embedding (genuine relatives). Analysis of this order of acquisition
shows that the first embeddings subjects make are shallower, which make them less
16
complex. Research shows that relatives which involve less embedding and
complexity and are (therefore) predominant in early developmental stages of
language learning typically developing children and also in some stages of atypically
developing children. The mean number of relative clauses produced is significantly
lower in mild-to-moderate hearing impaired children (the same is observed in
children with specific language impairment) than in the typically developing agematched children and adolescents. The rate of embedding increases with age, and
varies according to the severity of the impairment. The research emphasises the link
between computational complexity and the acquisition of relative clauses in typical
and atypical contexts. They consider complexity to be a linguistic concept, which
refers to syntactic movement and the depth of embedding (this will be discussed in
section 2.1).
Delage and Tuller (2009) focussed on the development of syntactic complexity.
First time testing (T1) results showed that among subordinate clauses, mild-tomoderate hearing impaired children and adolescents produced fewer relative clauses
than typically developing children. Comparison of the two age groups showed that
the younger mild-to-moderate hearing impaired subjects used less complex syntax
than older mild-to-moderate hearing impaired subjects. They produced less deeply
embedded clauses, more 0-level relatives and more non-finite embedded clauses
than older mild-to-moderate hearing impaired and typically developing children and
adolescents. Rate of embedding and MLU did not improve between T1 and T2. The
second testing point (T2) showed an increase of complex structures. Younger mildto-moderate hearing impaired subjects caught up adolescents with mild-to-moderate
hearing loss but their final performance remained lower than typically developing
subjects.
Besides the overall lower level of syntactic complexity in hearing impaired
adolescents another interesting finding was observed. Analyses of spontaneous
speech samples of atypically developing (children and) adolescents indicated
behaviours of avoidance of complexity by low production of complex structures, but
also by high frequency of failed attempts and alternative strategies, like direct
speech (Delage et al., 2008; Delage and Tuller 2009; for SLI see Hamann et al,
2007; Tuller et al. 2012). Instead of complex, subordinate clauses it was observed
that atypically developing adolescents used more direct speech (see example a) or
coordinated (juxtaposed) simple clauses (see example b) where they could have
used a main complex clause (Delage and Tuller 2009; for SLI see Hamann et al,
2007; Tuller et al. 2012). In the examples the subordinate sentences are placed
between brackets.
17
a) direct speech:
I)
You can say: “I want it faster.” instead of You can say [that you want it
faster].
b) juxtaposition of two clauses instead of subordination:
I)
I saw his friend he is nice, in stead of I saw his friend [who is nice].
c) self-interruption of a subordinate clause:
I)
Well, she is the girl [that…] … she is interested in sports games
II)
I think [that he... she yelled because] ...
Self-interruptions (example c) were observed to appear often in the spontaneous
speech of mild-to-moderate hearing impaired adolescents, more than in normal
hearing adolescents. In some cases of self-interruption the subordinate clause was
really abandoned (c I), where other self-interruptions were followed by a correct
subordinate clause (c II). In the first form of self-interruption it is clear that a
subordinate clause is aborted, and replaced by a main clause. For this example the
use of the term avoidance is appropriate. The second one is definitely not a form of
failed attempt, bur probably the result of self-correction. Researchers (Delage and
Tuller 2009; for SLI see Hamann et al, 2007; Tuller et al. 2012) do not distinguish
between the different forms of self-interruption, all calling them avoidance. This
makes this category ambiguous and less suitable to make statements about avoiding
complexity.
If complex subordinate sentences are harder to produce, it is likely that in these
syntactically complex sentences more errors will be made, especially in morphosyntax, than in simple(r) sentences. High error rates, indeed, are found in children
with mild-to-moderate hearing loss (Elfenbein et al., 1994), and remained very high
in adolescents (Delage and Tuller, 2009). There results showed that 21% of complex
utterances produced by all participants were erroneous versus 3% of those produced
by typically developing subjects (p <.001). And among the different types of
subordinate clauses, relative clauses were the most erroneous embedded clauses
18
(37% versus 19% erroneous finite complement clauses, 20% adverbial clauses). The
types of errors are not further specified in the research of Delage and Tuller (2009).
Tuller et all. (2012) who did similar research studying avoidance of complexity
and errors in spontaneous speech of adolescents with specific language impairment.
All morpho-syntactic errors were coded for syntactic category affected (root clause,
finite complement clause, non- finite complement clause, adverbial clause, relative
clause, or coordinate clause) and type of error (omission, addition, substitution, word
order). A higher percentage of complex clauses was erroneous when compared to
simple clauses, containing no subordination. These findings are consistent with the
expectation in syntactically complex sentences more errors will be made. Errors in
complex structures frequently entail avoidance of complexity. Avoidance of
complexity could also result in the use of generally simpler structures, which
increases the chances of production of error-free utterances. Tuller et al. (2012)
conclude that language patterns consisting of error rates but also frequency of
occurrence of complex structures and other avoiding strategies (e.g. direct speech)
in atypical populations can therefore provide evidence for lesser syntactic
complexity.
1.3 Summary and discussion
Sensorineural hearing loss entails not only lowered thresholds, bur also
distortion of the sound input. This results in language and speech recognition and
understanding that is partial and degraded. If a child is not exposed to auditory input
or the stimuli are not adequate during the critical period, it will never achieve a full
command of language. This means that many children with mild-to-severe hearing
loss are at risk for delayed language development, even after receiving hearing aids.
Summarizing the studies discussed in the previous sections, we can conclude
that language problems arise in all language areas (phonology, vocabulary,
morphology and syntax) in mild-to-severe hearing impaired children, problems that
remain into adolescence and adulthood. This means that language does not
normalize with age (Delage and Tuller, 2007). The biggest problems occur in the
most complex structures that are acquired during the latest stadium of language
development (Delage and Tuller, 2007, 2009; Delage et al., 2008). Analyses of
spontaneous speech samples of atypically developing (children and) adolescents
indicated behaviours of avoidance of complexity by low production of complex
structures, moreover in which more errors were made than in simple sentences.
19
Adolescents but also by high frequency of aborted sentences, failed attempts and
alternative strategies, like direct speech (Delage et al., 2008; Delage and Tuller
2009; for SLI see Hamann et al, 2007; Tuller et al. 2012). These findings provides
support for the hypothesis that mild-to-severe hearing loss has persistent effects on
language acquisition, and that these effects result in reduced syntactic complexity:
less frequent use of complex structures (whether or not by use of avoidance
strategies) and in higher error rates in complex structures compared to typicallydeveloping children and adolescents.
2.
Syntactic complexity
The previous chapter shows that hearing impairment can have major
consequences for language acquisition in all linguistic areas. There is no
normalization of language performance in adolescents with mild-to-moderate hearing
loss; more than half of the mild-to-moderate hearing impaired adolescents displayed
relatively severe long-term language impairment. These problems especially persist
in (morpho-)syntax, and seem to lie mostly in the last acquired most complex
structures of language. Syntactic complexity especially seems a sensitive indicator
for (persistent) language problems. The purpose of this chapter is to give a
theoretical description of the term syntactic complexity and how this can be
measured. This disquisition will be the foundation of my own empirical research as
will be described in Chapter 3.
2.1 Acquisition of syntactic complexity
Generally in the literature, language development and syntactic growth are
related to syntactic complexity. “Growth in complexity is perceived as an index of
development in linguistic abilities and therefore, complexity is an essential concept in
language acquisition studies” (Nieminen, 2009 p.173). During language development
children acquire syntactic structures that help them produce longer, refined and
more complex sentences. The knowledge of syntax increases rapidly during the
critical period, at the end of which all syntactic rules have to be obtained. Studies
that focus on language development have assumed that simpler structures are
acquired earlier in language development and that complex structures are acquired
later or cause long-term difficulties (Nippold et a., 2007; Smith 1988; Smith and van
Kleeck 1986; Hamann et al., 2007). In other words, this could mean that the order
of development can be identical to the order of complexity. In this section and
section 2.2 on subordination this issue will be addressed
20
With the emergence of finiteness, morphological rules (tense and agreement)
interact with syntactic rules. This expansion of syntactic abilities enables children to
express themselves better and more versatile. This goes along with overall
maturation of linguistic development (e.g. vocabulary expansion) and the
development of pragmatic rules. As their vocabulary and morphology increase and
children have more word forms and categories available (articles, question words,
conjunctions) their sentences become longer and more complex. In order of
acquisition children start to use main clauses, interrogative sentences, coordinations
and finally subordinations (Gillis and Schaerlaekens 2000). Syntactic constructions that emerge later in typical language development and
also emerge more slowly and/or cause problems in mild-to-moderate hearing
impaired children and adolescents can be characterized by a degree of higher
computational complexity (Hamann et al., 2007; Nippold et al., 2007), as will be
discussed later in this section and in section 2.2. Because of the increased linguistic
knowledge (vocabulary, morphology, syntax) and knowledge of the world, older
children, adolescents or adults can express their thoughts and experiences with more
complex words and phrases. Conversational turns, for example, become longer
(duration); sentences may consist of more communicative words, they may contain
combined syntactic structures (conjunction, embedding), and have different word
orders or contain movement. Compare the sentences presented in table 1.
Table 1. Four categories of the main sentence types, ascending in syntactic complexity
(Marinellie, 2004; Nippold et al., 2007; Nippold, 2010). 1. simple clauses
i. Yesterday I went to see Marie.
2. coordinate clauses
i. I went to her house, [but she was not at home].
3. complex (subordinated) clauses
i. [She was walking her dog], when it started to rain.
ii. [She was walking her dog], which she got for her birthday.
4. combined complex clauses
i. It is a very nice dog [that wags its tail], [whenever you stroke him]. 21
Simple (main/ root) clauses are the simplest type of sentences, containing (at
least) a verb and a subject. A coordinate clause, often referred to as a compound
clause, is a sentence that does not have embedded clauses, but at least two main
clauses joined by a coordinate conjunctions, including but, and, so and or (for
example but, see table 1, example 2.i). Complex clauses are sentences that
contain one main/ independent clause and at least one dependent clause, meaning
that they contain subordination. Combined complex clauses consist of the most
complex syntactic structures, being a combination of the sentence types mentioned
above: compound and complex combined or complex in complex, meaning a
dependent clause is embedded in another dependent clause. A complex hierarchy of
clauses, or syntactic complexity then occurs. When a subordinated clause is
embedded in another subordinated clause, which is embedded in a main (simple)
clause, a hierarchy of clauses occurs. The hierarchy is based on the levels of
embedding. In determining levels of embedding, all finite verbs in a sentence
represent a clause (Nippold, 2010). This means that from the sentences in table 1
example 1) contains one clause, 2) contains two (independent) clauses, 3) contains
two (1 independent and 1 dependent) clauses, 4) contains three clauses (1
independent, and 2 dependent). Note that there is not only a difference between the
number of clauses within these examples, but also in clause dependency. Referring
to table 1, 3) the complex clause, has 1 level of embedding consisting of one main
and one subordinate clause whereas 4) has 2 levels of embedding, one main with an
embedded clause, with an embedded clause in it. These latter two are examples of
one T-unit (which more extensively will be discussed in section 2.3.1) consisting of a
main clause and (one or more) subordinate clause(s) (Scott, 1988).
It seems logical that (most) errors will occur in spontaneous speech in the most
complex sentence types. These errors may lie in the field of dependencies
themselves, but also in complementizers mistakes or omissions, word order errors,
and lead to simplification and less computational complex (whether or not
ungrammatical) language (Hamann, 2007). Delage and Tuller (2009, p.2) state that
‘computational complexity’, within a generative framework, can be characterized by
three main factors set out in table 2. 22
Table 2. Three main factors of computational complexity by Delage and Tuller (2009, p.2).
•
the number of syntactic operations : ‘with the number of merges and presence or
absence of movement’ •
the nature of syntactic operations: ‘merge versus movement, distance of dependency
relations and/or the nature of intervener in such relations.’ •
the depth of embedding: …’deeply embedding constituents increase the cost of the
syntactic computation’ With ‘merge’ is meant the operation when two syntactic objects are combined to
form a new syntactic unit (Chomsky, 2001). This is divided into external merge when
the entities are two separate objects and internal merge when one of them is part of
the other. Movement as explained by Carnie (2006) is the fact that certain
constituents appear to have been displaced from the position where they receive
important features of interpretation (for example movement of the subject or the
object to preverbal position in interrogatives). With depth of embedding means
subordinate clauses embedded in main clauses for different levels (Nippold, 2010).
Compare the following two examples (5 and 6): 5)
I take a card. 6) You can ensure [that a person [who has only one card] has to take a card]. In sentence 6 compared with sentence 5 we see a much more complex sentence
structure, involving:
-
merge: which in sentence 5 for example exists of the verb selecting a subject
and an object, whereas the main verb in sentence 6 selects a subject and a
direct object in the form of a nominal subordinate clause that has the function
of a noun phrase.
-
movement: Sentence 5 is a simple clause that does not involve movement. In
sentence 6 the Wh-word (who) used in relative clauses is moved to the front
of the clause.
23
-
depth of embedding: sentence 5 only consists of one main clause, whereas
sentence 6 consists of a main clause, a nominal subordinated clause that is
selected by the main clause and a relative clause embedded in the nominal
subordinate clause.
2.2
Subordination
Subordination has been seen as an important developmental step making the
transition from simple to complex sentences. Subordination is defined as a
dependent clause within another sentence (Gillis and Schaerlaekens 2000) with the
function of a noun, adverb or adjective in a resultant complex sentence. The initial
phase of subordination is when children start to use preconjunctional subordinate
clauses that lack the complementizer (Penner and Muller, 1992). From there they
start to acquire the adult language system with the syntactic knowledge that
requires the use of complementizers (Armon-Lotem, 2005). At the end of the critical
period (Lenneberg et al., 1967) typically developing children have acquired all types
of subordination, regardless of whether or not they are used correctly. Sometimes
they still lack a complementizer or have main clause word order). Nippold in her
studies (Nippold, et al. 2005 and Nippold, 2009) distinguishes three different (main)
types of subordination (see table 3).
Table 3 Three categories of the main subordinate clause types. Examples are complex
clauses consisting of a main clause and a subordinate clause (placed between brackets)
(Nippold et al., 2005, 2009).
-
adverbial clause: a phrase that functions as an adverb in a sentence.
vb. The dog never barks, [when I pat him].
-
nominal clauses: a subordinate clause that functions as an obligatory
constituent of the main phrase.
vb.
-
Marie knows [that her dog will not bark at acquaintances].
relative clause: a subordinate clause that modifies a noun phrase (most
commonly a noun).
vb. I once heard him bark to the postmen [who entered the yard].
24
Earlier we concluded that simpler structures are acquired earlier than more
complex structures. There is no doubt that these sentences (see table 3) are more
complex than simple root clauses (see section 2.1) and they thus have to be
acquired last. The order of acquisition of the different subordination types could
provide information about the complexity of each individual type of subordinate
clauses. Within the linguistic field there is some discussion about the order of
acquisition of these different types of subordinate clauses for different languages,
most likely due to cross-linguistic differences (Bowerman 1979; Bloom et al. 1980;
Penner, 1995; Dromi and Berman 2008). As far as know for Dutch no data are at
hand about the acquisition order of the different types of subordinate clauses.
Although the expectation is that all adult subjects will have acquired all the syntactic
structures, knowledge about the acquisition order could have been helpful to predict
which type of subordinate clauses is last acquired and therefore will be most
problematic (and therefore less produced, more erroneous or avoided) in hearingimpaired adults.
What can be seen from the various subordinate structures is that the nominal
subordinate clause forms a part of the main clause, and so is represented in the
surface structure. It refers to one layer of embedding, as the sentence is selected by
the verb phrase, and also embedded in the verb phrase (VP). The clause is a
complement to a main clause and is in itself a noun phrase (NP) in the VP. The
adverbial subordinate clause is different from the nominal subordinate clause.
Adverbial subordinations are not required by a verb (form no argument of the
predicate), but are an addition to the main clause, and they are therefore called nonselected. An adverbial clause is a single sentence in the main clause and also
involves one layer of embedding. The relative clause is also a non-selected
embedded clause, which on its own involves one layer of embedding. Based on their
research Delage and Monjauze (2008) and Delage and Tuller (2009) considered this
to be the most complex type of subordination due to: significantly lower mean
number of relative clauses produced in mild-to-moderate hearing impaired compared
to typically developing children and adolescents, and participants avoiding relative
clauses by using a simple clause.
25
2.3
Measuring syntactic complexity
This thesis will look at syntactic complexity from a language-based perspective
(Nieminen, 2009). This means that the language itself is the starting point and that
application of language and the language user are disregarded. This implies that
statements on this form of syntactic complexity hold for both children and adults,
typically or atypically developing, because it is independent of the language user.
This absolute approach of linguistic complexity views complexity from an objective
and linguistic theoretical perspective, as a measurable linguistic feature. Studies on
syntactic growth and syntactic complexity show the use of different measures to
measure language development and linguistic complexity in a-typically developing
children, adolescents and adults (Hunt, 1970; Delage & Tuller, 2007; Hamann et al.
2007; Marinellie 2004; Nippold et al., 2005, 2007, 2008; Nieminen, 2009). The main
measures used are Mean Length of Utterance or T-unit (counting length), and type
and number of embeddings on the basis of which clausal density is measured (also
called ‘subordination index’). These measures will be described in the following
sections (2.3.1 and 2.3.2).
2.3.1 Mean Length of Utterance
Mean Length of Utterance (MLU) is the first way of measuring language
development and is often used to identify language impairment. MLU is based on the
idea that “… almost every new kind of knowledge increases length: the number of
semantic roles expressed in a sentence, the addition of obligatory morphemes,
coding modulations of meaning, the addition of negative forms and auxiliaries used
in interrogative and negative modalities, and of course, embedding and coordination”
(Brown, 1973, p.53-54). MLU can be measured by counting the morphemes or
words per utterance, communicative unit (C-unit), or terminable unit (T-unit)
(Nippold, 2010). A T-unit is defined as an utterance that must contain one main
clause and optionally may contain one or more subordinate clauses (Scott, 1988).
The difference between Mean Length of T-unit and Mean Length of C-unit is that in
the latter all communicative expressions are counted, also when they lack an
independent clause (Loban, 1976) for example, the answer ‘‘no’’ to the question ‘‘Do
you play basketball?’’ is counted as a C-unit). MLU calculations can vary in many
ways and the results are not unambiguously cross-linguistically comparable
(Nieminen, 2007).
26
The validity of the mean number of morphemes or words, per sentence or per
shorter linguistic unit, as a measure of language development is supported and has
been proved useful for analysing spontaneous speech in young children (Hunt, 1970;
Loban, 1976; Bol and Kuiken, 1988). Research results show a slow but steady
growth of MLU throughout childhood and adolescence into adulthood and show that
MLU measures for atypically developing children are overall lower than for normal
developing children. Mean length of T- (or C-) unit is considered to be an important
marker of later syntactic complexity (Hunt,1970; Loban,1976; Nipoold, et al., 2005).
As Nippold et al. (2005) suggest, the Mean Length of T-unit gives us information
about the unit length, and combined with the amounts of different sentences types
(coordinate clauses and subordinate clause types) can provide information about the
ratio between sentence length and number of embedded clauses. This provides
insights in complexity of sentences of language users. This would imply that it can
reveal possible differences is the production of subordinate clauses between normal
hearing and congenital hearing impaired adults.
2.3.2 Clausal densities
As described above, a sentence can consist of several T-units, that each consist
of an independent (main) clause and possibly contain one or more dependent,
subordinate clauses. Besides Mean Length of T-unit some studies show that clausal
density is another indicator of syntactic complexity (i.a. Nippold, 2005). The total
number of T-unit combined with the amounts of different sentences types can
provide information about the clausal density, an important marker of later syntactic
development. Clausal density, also referred to as subordination index, is defined as
‘‘the average number of clauses (main and subordinate) per T-unit’’ (Scott, 1988, p.
58). It is measured by summing the total number of clauses (independent +
subordinate), divided by the total number of T-units produced in a language sample.
Clausal density, is the ratio of the number of (in)dependent sentences per T-unit
produced.
During language development children formulate sentences more efficiently,
while making increasingly more use of subordinate clauses. This means that clausal
density increases during language development. Clausal density has showed agerelated increases and therefore has proven to be a good indicator for growth of
syntactic complexity (Nippold et al., 2005, 2008; Nippold, 2009). In atypically
developing children it has been shown that they make us of simpler sentence
structures longer and make less use of subordination (Delage and Tuller, 2009;
27
Tuller et al., 2012). This tendency also seems to continue in atypically developing
adolescents (with mild-to-moderate hearing impairment or specific language
impairment) and it would be a logical assumption to see the same in adults who
have had an atypical language development. A person who produces little or no
subordinate clauses, and thus syntactically less complex language than a person who
produces many subordinate clauses, will have a lower clausal density.
In several studies (Nippold et al., 2005, 2008; Nippold, 2009), in addition to the
distinction between independent and dependent, a distinction also has been made
between the different types of subordinate clauses. (The contents of this
subordination classification and its implications for syntactic complexity have been
discussed in sections 2.1 and 2.2.) For these sentences types separately a density
can be calculated by summing the total number of main clauses + the specific type
of subordinate clauses, divided by the total number of T-units. This results is a
nominal clausal density (NCD), adverbial clausal density (ACD) or relative clausal
density (RCD). Of all these clausal densities Nippold et al. (2005) stated that relative
clausal density must be considered to be a better measure for syntactic complexity
than clausal density, nominal clausal density and adverbial clausal density, because
this variable is the most sensitive to growth (together with Mean Length of T-unit)
and reveals more differences between normal hearing subjects of different ages
(children, adolescents and young adults).
Although the language of the subjects that participate in my study is mature, it
is likely to find differences in the relative clause production between moderate-tosevere and normal hearing adults. Simple relative clauses are produced in children
but much more by adults, who have access to the full range of relative clause types.
Given their possibly delayed language development due to their congenital hearing
impairment, it is quite possible that moderate-to-severe adults will experience
problems in the production of subordinate, and specifically relative, clauses. The
clausal densities within this research can provide information about syntactic
complexity of moderate-to-severe adults compared to normal hearing adults who
had a typical language development.
2.4
Research questions
The preceding sections have shown the importance of optimal exposure and
access to language input early in life. It has been argued that when a child cannot
fully benefit from the language input from his environment during the critical period,
it is at risk of language problems. These problems occur in different aspects of
28
language, but predominantly in the areas of phonology and (morpho-) syntax.
Language does not normalize with age in people with mild-to-moderate hearing loss.
(Delage and Tuller 2007). Previous research (Delage et al., 2008; Delage and Tuller
2007) has shown that hearing impaired children and adolescents show syntactically
less complex language than normal hearing people. Subordination, and especially
relative clause constructions, is considered to be the best indicators for the
acquisition and growth of syntactic complexity in the spontaneous speech of typically
and atypically developing children and adolescents. (Nippold et al. 2005; Nippold et
al. 2008). Both these indicators showed an age related increase, meaning that
younger children, when they become older, use more and more subordination and
especially relative clauses. This increase continues into early adulthood (Nippold et
al. 2005). Analyses of spontaneous speech samples showed behaviours of avoiding
complexity by low production of complex structures, frequency of failed attempt and
alternative strategies in hearing impaired children and adolescents (Delage et al.,
2008; Delage and Tuller, 2009).
Although several studies have investigated the syntactic complexity in typically
and atypically developing children and adolescents, there are no studies known on
the syntactic complexity in impaired adults, comparing them to normal hearing
adults. Because the effects of hearing impairment on language acquisition and
speech remain later in life, it is plausible that moderate-to-severe congenital hearing
impaired (MSCHI) adults still encounter problems in reduced syntactic complexity,
avoidance strategies or more erroneous (complex) sentences (Delage et al., 2008).
The aim of this thesis is thus to investigate the syntactic complexity, measured
by subordinated and specifically relative clause production, errors related to
embedding occurring subordinate clauses, and possible avoidance patterns and
compensatory strategies in congenital hearing impaired Dutch adults. The studies by
Nippold et al. (2005, 2008, 2009) and Delage et al. (2007, 2008) as described in the
previous sections will serve as a theoretical framework for my empirical research.
Based on these researches the following research questions will be addressed in this
thesis:
Research questions:
1.
Do adults with a congenital, moderate to severe hearing impairment
produce less complex language than adults with normal hearing?
a.
Do adults with a congenital, moderate-to-severe hearing impaired
produce shorter utterances than adults with normal hearing?
29
b.
Do adults with a congenital, moderate-to-severe hearing impaired
have a lower clausal density than adults with normal hearing?
c.
Do adults with a congenital, moderate-to-severe hearing impaired
have a lower relative clausal density than adults with normal
hearing?
d.
Do adults with a congenital, moderate-to-severe hearing impaired
have a lower nominal clausal density than adults with normal
hearing?
e.
Do adults with a congenital, moderate-to-severe hearing impaired
have a lower adverbial clausal density than adults with normal
hearing?
2.
Do adults with a congenital, moderate-to-severe hearing impairment
make more errors than adults with normal hearing?
3.
Do adults with a congenital, moderate to severe hearing impairment use
avoidance strategies more than adults with normal hearing?
I will propose the following hypotheses about the syntactic complexity in
moderate-to-severe hearing impaired adults.
Hypotheses:
1) Normal hearing adults will produce more syntactically complex language than
hearing impaired adults and therefore have a higher clausal density and relative
clausal density.
2) Clausal density of normal hearing adults to be higher than the density of
moderate-to-severe hearing impaired adults.
3) Relative clausal density will be higher than clausal density and provide a better
distinction between normal hearing adults compared to moderate-to-severe hearing
impaired adults, and will therefore be a better measure for syntactic complexity than
clausal density.
4) The spontaneous speech of moderate-to-severe hearing impaired adults will
reveal avoidance patterns, to avoid syntactically complex structures. Avoidance of
syntactic complexity will be higher in moderate-to-severe hearing impaired adults
than in normal hearing controls and will affect the most complex structures.
30
5) Moderate-to-severe hearing impaired adults will make more morpho-syntactic
errors in syntactically complex structures than normal hearing controls.
2.5
Summary and discussion
In the preceding sections a theoretical and operational approach of syntactic
complexity have been presented. Language development and syntactic growth are
related to syntactic complexity, because growth in complexity is perceived as an
index of development in linguistic abilities (Nieminen, 2009). This implicates that
order of acquisition might be identical to the order of complexity. Syntactic
constructions that emerge later in typical language development and also emerge
more slowly and/or cause problems in mild-to-moderate hearing impaired children
and adolescents can be characterized by a degree of higher computational
complexity (Nippold et al., 2007; Hamann et al., 2007). Syntactic complexity
especially seems a sensitive indicator for (persistent) language problems.
Subordinate clauses are the last syntactic structures to be acquired and considered
to be the most complex syntactic structures, in which persistent language problems
remain visible. Syntactic complexity is operationally determined by the increasing
production of the Mean Length of T-unit, clausal density, and subordinate clausal
densities (nominal clauses, adverbial clauses, and relative clauses) (Nippold et al.,
2005; Nippold et al., 2007; Nippold et al., 2008). Mean length of T-unit and relative
clausal density are considered to be the best measures for syntactic complexity
(Nippold et al., 2005).
Based on these data research questions and hypotheses are formulated on the
syntactic complexity of moderate-to-severe hearing Dutch speaking adults. These
will form the core of the research presented in the following chapters (chapter 3 and
4).
31
3
Method
3.1
Participants
For the project (pilot-study) of Elke Huysmans and this research Elke and I
agreed on using the same test group. Together we recruited normal hearing adults
(N=10) via an advertisement via e-mail, which was distributed to our friends and
acquaintances. Moderate-to-severe hearing impaired adults (N=20) were all patients
in the VU medical centre, KNO-audiology, they were approached for voluntary
participation in the study. The VU Medical Centre medical ethics approved the study.
When investigating the syntactic complexity of congenital hearing impaired
adults, it is important to study the language of subjects with a minimum age of 20
years and a maximum age of 40 years. Studies show that at the age of 20, language
proficiency in the normal population is well established. Nippold et al. (2005) studied
the syntactic complexity of the spontaneous language of normal hearing people with
different ages (7-49 years) and concluded that syntax continues to develop beyond
adolescence and into early adulthood (20-29 years), but remains stable in middle
age (40-49 years). There is no evidence for continued growth beyond early
adulthood. Therefore, the minimum age of the subjects was set at 20 years. The age
of the subjects was limited at 40 years to prevent the interference of deteriorating
auditory functions as a result of age (presbyacusis).
For all normal hearing participants hearing was tested calculating the pure-tone
average (PTA), using an exclusion criterion of a pure tone average of 20 dB on the
best ear (see section 1.1 for Fletcher Index; average number of decibels by 500,
1000, 2000 Hz). For some moderate-to-severe congenital hearing impaired subjects
a recent audiogram was filed in their medical record, for others a new audiogram
was made, handling a pure tone average of 35 dB on the best ear. Based on a
combination of anamnestic questionnaire and audiometric data it was clear that all
congenital hearing impaired adults were hard of hearing (35 to 95 dB HL) from birth.
People with additional problems such as a diagnosed cognitive delay (IQ<80),
specific language impairment or psychiatric disorder (e.g. ADHD) were excluded. For
an overview of the characteristics (FlI, hearing rehabilitation and education) of the
participants see table 4.
32
Table 4 Overview of the characteristics of the normal hearing and moderate-to-severe
NH01
NH02
NH03
NH04
NH05
NH06
NH07
NH08
NH09
NH10
HI 01
HI 02
HI 03
HI 04
HI 05
HI 06
HI 07
HI 08
HI 09
HI 10
HI 11
HI 12
HI 13
HI 14
HI 15
HI 16
HI 17
HI 18
HI 19
HI 20
20
24
21
22
24
34
26
34
24
20
33
34
27
31
21
32
20
20
24
25
39
34
23
30
29
45
23
20
24
28
18
2
2
8
18
2
3
5
5
3
58
93
88
50
50
83
35
90
68
52
108
78
50
102
88
107
57
95
102
83
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
no
no
no
no
no
yes
no
yes
no
no
yes
no
no
yes
no
yes
no
yes
yes
yes
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
n.a.
HA
CI
HA
HA
HA
HA
HA
HA
HA
HA
CI
HA
HA
HA
HA
CI
HA
CI
HA
HA
H
H
H
M
M
M
M
L
M
L
H
H
H
H
M
H
L
H
H
H
M
H
H
H
M
L
M
L
M
M
Special e secondary education
Special primary education
level of education
current type of hearing
rehabilitation
Progressive hearing loss
current PTA 500-1000-2000 best ear
age
subject
congenital hearing impaired subjects participating in this study.
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
All participants had Dutch language as their mother tongue, were monolingual
(some moderate-to-severe hearing impaired adults had had special education for
hearing impaired, but had not been exposed to a sign language) and were at least
VMBO-T educated (Lower General Secondary Education/ UK GCSE's at C level). The
33
overall educational level of the participants in this study was matched with the
distributions of the general education levels of the Dutch population; meaning all
levels of education were represented (low (L), middle (M) and high (H)) with more
middle and low educated participants than highly educated. The attempt was to form
two groups (normal hearing and moderate-to-severe hearing impaired) that were
equal for educational level. For the normal hearing group the distribution of
educational level is L=20%, M = 50% and H=30%. For the moderate-to-severe
hearing impaired group the distribution of educational level was L = 15% M=30%
and H=55%. Unfortunately Elke Huysmans and I did not fully succeed, ending with
the hearing impaired group being slightly higher educated than the normal hearing
group.
3.2
Data collection
All participants were subjected to a test battery, consisting of an interview
eliciting a spontaneous speech sample (to obtain data for both Elke Huysmans
(Huysmans et al., to appear) and my own project), the CELF-4 NL test (Clinical
Evaluation of Language Fundamentals, Semel et al., 2008) (to provide (not
standardized) data about the subjects overall language abilities for the project of
Elke Huysmans) and a writing task (for follow-up research within the project of Elke
Huysmans on writing skills in hearing impaired adults (Groenestyn, 2011). The
testing procedure and results on the latter two tests/ observation instruments are
not included within the research presented here. For examining the syntactic
complexity within this thesis I decided only to examine and analyze the spontaneous
speech samples, expecting that these would provide the most complete view of the
language ability and syntactic complexity of the subjects.
To measure syntactic complexity it is necessary to elicit language from subjects
that is suitable for analyses. Spontaneous speech samples were elicited by
interviewing the participants about their favourite game or sport. Nippold (2005)
showed that this task is a good way to trigger expository discourse. Expository
discourse is the use of language to convey information in the form of a monologue
(Bliss, 2002). This discourse genre has proven to be more effective for eliciting
complex syntax in typically and atypically developing people than narrative or
conversational discourse. Verhoeven et al. (2002) found that in Dutch, English,
French, Hebrew, and Spanish grade-school children and adults all kinds of subordinate
clauses occurred more often in expository discourse than in narrative texts. Nippold
34
(2005) found that the language of children as well as of adolescents and adults was
more complex in expository discourse than in conversational discourse. Especially
relative clause production was very sensitive to discourse type; adults showed this
type of subordination more often in expository discourse than children.
Based on these results within this project the method of Nippolds ‘favourite
game or sport task’ (2005) exactly was used to obtain our language samples. The
questions posed to the subjects are shown in table 5.
Table 5: Questions eliciting expository discourse in the ‘favourite game or sport task’ (FGST)
(Nippold, 2005, p.152)
A. "What is your favourite game or sport?
B. "Why is [x] your favourite sport?"
C. "I’m not so familiar with the game of [x], so I would like you to tell me all about it. For
example tell me what the goals are, how many people play the game. Also tell me about the
rules that players need to follow. Tell me everything you can think of about the game of [x]
want you to assume that I know nothing about (x), so that someone who has never played
before will know how to play.
D. Now I would like you to tell me what a player should do in order to win the game of [x]. In
other words, what are some key strategies that every good player should know?
All interviews were conducted by the same two researchers, strictly following the
questionnaire to prevent differences in questioning, and were audio taped for later
transcription. The first two questions (A and B) were asked to introduce the topic of
the conversation and make the person feel at ease; they elicit conversational
discourse. Questions C & D were asked to elicit an expository discourse and to elicit
complex language use. For this purpose we asked our subjects to describe a
competitive sport, whereby they had to explain the rules of the game carefully so
that the investigator would understand. There was no time limit, but participants
were challenged to tell as much as possible about their chosen sport. Spontaneous
speech that was elicited by these last two questions (C and D) was used for analysis.
35
3.3
Analysis
All language samples were transcribed using the principles for sentence
segmentation of the STAP procedure (van den Dungen and Verbeek 1999). For
analysis, only free expressions (= all sentences that are no answers to question,
consisting of a single main clause, and (optionally) one or more subordinate
sentences) were taken into account, because they contain by the subject selfformulated sentences. Elliptical utterances (= answers referring to an (indirect)
question, and often an elliptical sentence) were left out of the analysis, even as nonfluent speech: false starts, incomplete sentences, and (word) phrase repetitions
(STAP-procedure, van den Dungen and Verbeek 1999, p. 13-17).
Samples were analyzed for T-units (see section 2.3.1). Marinellie (2004) found
that a sample of 100 utterances (in conversational discourse) yields a reliable and
representative sample, yielding examples of all complex sentence structure of
interest (compound, nominal, adverbial and relative clauses, for examples see
section 2.1 and 2.2 (table 3). The aim of this study was to collect a language sample
of at least 50 T-units spontaneous speech in expository discourse per subject. The
expectation was that a minimum of 50 utterances in expository discourse would yield
a representative sample comparable with 100 utterances in conversational discourse.
Although in many cases the ‘favourite game or sport task’ resulted in an expanded
speech sample, some subjects produced fewer than 50 T-units. There was a large
variation in sample sizes, ranging from 23 to 211 T-units (normal hearing 47-76;
moderate-to-severe hearing impaired 23-211). This brought a dilemma about
whether or not excluding the smallest samples within the limited test group. Even
the norm of 40 T-units would have meant exclusion of 5 subjects.
All T-units were analyzed for presence of compound clauses and subordinate
clauses, subcategorized by nominal, adverbial and relative subordinate clauses
(following the procedures of Hunt, 1970 and Nippold, 2005). Some small samples
contained all types of complex sentences (for example CHI produced 26 T-units
containing all types of complex syntactic structures), while in larger samples this was
not the case (NH1 produced 76 T-units, with no relative clause). Nevertheless, all
participants produced at least 3 out of 4 complex sentence structures. This implies
that the smaller samples need not be of less value and should not be inferior to
larger samples when it comes to complexity. Given this, it was decided to include all
subjects analyzing the samples to a maximum of 100 T-units. Because not all
samples contained the same number of t-units and length of the speech sample
36
differed too, all primary data are calculated into averages and percentages to be able
to compare all group outcomes (see table 6).
Table 6 The averages and percentages of the primary data (total number of T-units,
compound clauses and subordinate (subdivided into nominal, adverbial and relative clauses) of
normal hearing and hearing impaired adults.
NH
Total T-
(N=10)
unit
%
%
%rel cl
% adv cl
% Nom
Compound Subordinate
clause
cl
clause
Mean
62,5000
31,0000
23,1000
17,2920
49,9040
32,8050
Median
61,0000
26,5000
23,0000
20,8350
49,7750
36,3950
11,05793
13,10640
8,19824
13,52910
17,06921
8,28438
% adv
% Nom
cl
cl
Std. Deviation
MSCHI
Total T-
%
%
(N=20)
unit
Compound
Subordinate
clause
clause
%rel cl
Mean
72,9500
29,9500
21,0500
18,5145
48,5252
32,9605
Median
58,5000
30,0000
18,0000
17,2650
50,2600
29,2750
53,16655
14,46038
8,75680
13,6379
22,0486
17,4893
7
3
5
Std.
Deviation
3.3.1 Syntactic complexity
As described in section 2.3.1 and 2.3.2, there are several important measures
for measuring syntactic complexity: Mean Length of T-unit, clausal density and
subordinate clausal densities. These measurements were used in this study to reveal
difference in syntactic complexity between moderate-to-severe hearing impaired and
normal hearing adults. Below a brief explanation of these measures and the
calculation methods will be presented.
A. Mean length of T-unit (MLU)
In order to be able to answer research question 1.a (see section 2.4), if
congenital, hearing impaired adults produce shorter sentences than normal hearing
37
peers, the Mean Length of T-unit (see section 2.3.1) was calculated (Hunt, 1970).
This was done using the following calculation:
Total number of communicative words : total number of T-units = Mean Length of
T-unit
B. Clausal density (CD) or, subordination index
In order to be able to answer research question 1.b (see section 2.4), if clausal
density is lower in moderate-to-severe hearing impaired adults than normal hearing
adults, the clausal density (see section 2.3.2) was measured. This is a measure of
syntactic complexity that produces a ratio of the total number of clauses to the total
number of T‐units, resulting in the average number of clauses, main and
subordinate, per T-unit (Scott, 1988, p. 58). Clausal density was measured by using
the following calculation:
total number of main clauses + total number of subordinate clause
(NOM+ADV+REL) : total number of T-units = clausal density
C. Subordinate clausal densities
In order to be able to answer research questions 1.c, d and e, if the different
subordinate clausal densities are lower in moderate-to-severe hearing impaired
adults than normal hearing adults, the clausal densities (see section 2.3.2) for every
subordination type were calculated separately. This was done using the following
calculation:
total number of main clauses + total number of dependent clauses of a specific
subordination type (nominal adverbial or relative): total number of T-units =
subordinate clausal density
Depending on the type of subordination used in the calculation, you can measure
nominal clausal density (NCD), adverbial clausal density (ACD) and relative clausal
density (RCD). Comparison of these densities would constitute evidence for the
hypothesis 2 (see section 2.4), that relative clausal density shows greater differences
between normal hearing and hearing impaired adults and therefore a better measure
than the other densities (clausal, nominal and adverbial).
38
3.3.2 Errors
Studies on complexity in mild-to-moderate hearing impaired (Delage et al.,
2008; Delage and Tuller, 2009) and specific language impaired subject (Marinellie,
2004; Tuller, 2012) show that atypically developing children and adolescents make
more errors than normal hearing pears. Errors occur mainly in the most complex
sentences types. In existing studies on syntactic complexity in atypically developing
subjects examples of errors are presented, but the different types of errors are not
clearly classified.
To provide an answer to research question 2, if moderate-to-severe hearing
impaired adults make more errors than normal hearing adults, all subordinate
clauses were analyzed for errors. Only subordinate clauses were analyzed, and not
main clauses, because these clauses are considered to be the most complex
structures, and therefore most susceptible to errors. Because errors categories based
on literature were not available, it was decided to create ad hoc categories, based on
the different types of errors that occurred in the analyzed subordinate clauses.
Standard Dutch language was used as a starting point to test the grammaticality of
all subordinate clauses. Language forms and constructions that differed from the
standard Dutch, even if these errors within a regional dialect possibly could be
considered as correct language, were reviewed as errors.
Errors were categorized in errors inside and outside the subordinate clause
structure. Word order errors (embedded V2) and errors in, or omission of
demonstrative pronouns and complementizers that directly influenced the
subordinate clause structure were considered to be errors inside the subordinate
clause structure. All other errors were classified as errors outside the subordinate
clause structure. The different error categories, with corresponding examples are
listed below.
1) Wrong relative pronoun:
*het doel [dat is een rechthoek [wat
the goal that is a
rectangle
what
rechtop staat]]
upright stands
met een net erin
with a
net in.it
“The goal is a rectangle that stands upright with a net in it.”
39
2) pronoun deletion:
*Dus als ‘t iemand
So
if
van
je
eigen team is ø [de bal uitschopt], dan …
it someone from your own
team is ø the ball kicks
, then
"So if it is someone from your own team who kicks the ball, then …”
3) wrong complementizer:
*als het zijn fout
If
it
his
is, ødoor de bal in de eigen veld terugkomt
fault is, ø.by
the ball in the own
,dan…
field comes.back ,then…
“If it is his fault, causing the ball to fall back into the own field, then…”
4) complementizer deletion:
*maar [ø bijvoorbeeld de tussenstand
But
nog vijf vijf is] …
ø for.example the intermediate.position still five five is …
"But for example when the intermediate position is still five five ...”
5) embedded verb second (V2) clauses
Embedded verb second clauses (V2) are embedded clauses (nominal and
adverbial) with main clause word order (the verb in second position). A
negative element in the main clause makes the embedded V2 impossible.
Embedded V2 clauses can only be preceded by the complement omdat
‘because’ if the given reason in the embedded clause is an established fact
(Zwart, 2011, p. 123/ 124).
*maar waar
but
het om gaat is wie is de
where it
snelste na
die twintig ritten
to goes is who is the fastest after this twenty tours
“But what matters is who is the fastest after twenty tours”
All other ‘outside subordinate clauseerrors made by the subjects that could not
be grouped into any of the categories described above (e.g. errors in verb
conjugations, plurals, omissions of articles) were classified as errors outside the
subordinate clause structure. These errors, within this research, were not further
specified (for a complete analysis off all the morpho-syntactic errors made by the
40
normal hearing and hearing impaired adults in the same spontaneous speech
samples see Huysmans et al., to appear).
3.3.3
Avoidance of syntactic complexity and compensatory strategies
In order to answer the third research question, if moderate-to-severe hearing
impaired adults use more avoidance and compensatory strategies than normal
hearing adults, the spontaneous language samples for both groups were analyzed for
avoidance and compensatory strategies. The researcher examined the sentences in
which a subordinate clause structure could have been used, but where another type
of sentence construction was used instead of subordination. In section 1.2.2 different
avoidance strategies (e.g. direct speech, juxtaposition) have been described that
have been discussed in the literature. It was noted that the term avoidance is not
entirely uncontroversial, and some categories are ambiguous.
Based on literature and examples from the samples unambiguous categories of
avoidance were formed. Sentences constructions that did not fall within these
categories, such as ambiguous sentences (due to complex mixing constructions
where the meaning of the sentence was not clear) are excluded for analysis on
avoidance.
1 ) Direct speech:
Direct speech is a representation of words or an expression of a person in
the form of a quotation (Vandeweghe, 2004 p.280). Instead of direct speech
a nominal subordinate clause could have been used. Compare the examples
1 and 2, where 1 represents direct speech and 2 a main clause with nominal
subordinate clause:
1.
You can say: “I want it faster”.
2.
You can say [that you want it faster].
Compared to a subordinate clause, direct speech lacks a complementizer
and has V2 word order (instead of the subordinate word order where the
verb occurs at the end of the sentence), and thus is considered to be less
complex. Use of direct speech could therefore be a strategy used by hearing
impaired adults to avoid complexity.
41
2) Verb first subordinate clauses
Verb first (V1) constructions are subordinate constructions where the first
constituent is not a subject, but the first place in the sentence is filled with a
finite verb. This type of subordination was only found in conditional clauses
with an adverbial if … then-constructions. In Dutch subordinate clauses the
final verb occurs in final position. In Verb 1 subordinate clauses the verb
precedes the subject, occurring in sentence initial position, the position that
in a normal subordinate clause would be filled with a complementizer or
relative pronoun. In Verb 1 subordinate clauses the complementizer if is
omitted. Compare example a, a sentence with verb 1 construction, with
sentence b, where the same sentence (with same meaning) with normal
subordinate word order is presented.
staat het paard scheef dan krijg je
does the horse lean
than get
minder punten
you less
points
“does the horse lean, then you get less points”
This sentence type is considered to be less complex, because of the missing
subordinate word order and the absence of a complementizer.
3) Clausal conjunction
Clausal conjunctions are sentences that resemble a relative clause
construction, but have the verb in second position (V2). Other than verb
second constructions in nominal and adverbial (see the description of the
error categories in this section), clausal conjunction in relative clauses does
not (necessarily) lead to an ungrammatical sentence. Instead of a main
clause with a subordinated relative clause it results in two simple main
clauses in juxtaposition. The relative pronoun loses its function of initiator of
the subordinate clause, but has the function of a demonstrative pronoun.
Compare the following two sentences where 1 represents an example of a
relative clause construction and 2 shows an example of clausal conjunction:
1) dat is een mannetje [die dan
that is a
guy
buiten die
teams staat]
who then outside these teams stands
“that is the guy who then stands outside these teams”
42
2) dat is een mannetje, die
that is a
guy,
staat
dan buiten
die
teams”
who stands then outside these teams
“that is the guy who then stands outside these teams”
In the last sentence the word die is not a relative pronoun but a
demonstrative. Compare sentences 3 and 4:
3) dat is een mannetje waar
that is a
man.little where
iedereen bij wil
horen
everyone to wants join
“That is a little man who everybody wants to join”
4) dat is een mannetje (en) daar wil
that is a
man
iedereen bij horen
(and) there wants everyone to join
“That is a little man everybody wants to join”
The noun phrase specified by the specifying coordinated clause must be
non-specific (unlike the relative construction). Also the first part of the
sentence cannot be a question, command, or contain a negation or an
intentional verb. No such restrictions apply to regular relative constructions
(Zwart, 2011, p.126).
4.
Results
In this chapter the results from the analyzed data of the spontaneous language
of moderate-to-severe congenital hearing-impaired and normal hearing adults will be
discussed. First, a ‘test for normality’ (Kolmogorov- Smirnov) was done for all
variables to see if the data were normally distributed. All important variables were
not normally distributed, as a logarithmic test also showed. The Mann Witney-U test,
a non-parametric tests for independent samples, was therefore used for statistical
analysis.
As discussed in section 3.3 the samples varied considerably in number of
utterances. For the normal hearing group this range was between 47-76, with a
median of 61.0 utterances. For the hearing impaired group the range was between
23-211 utterances, with a median of 58.5 utterances. There was no significant
difference in group size between the hearing impaired and normal hearing adults
[Mann-Whitney U = 81,000; NH = 10, MSCHI = 20, P> 0.05].
43
The results that will be discussed in the following sections, 4.1 to 4.3, will show
whether there are differences between the both groups on syntactical complexity,
error rates and avoidance strategies and if and how these results on statistical
analysis provide answers to the research question as formulated in section 2.4. For
both groups all variables and data are reported in appendix III.
4.1 Results for syntactic complexity
Syntactic complexity was measured by 6 variables: mean length of utterance
(MLU), mean length of the 5 longest utterances (MLUL), clausal density, nominal
clausal density, adverbial clausal density and relative clausal density. Results on
these variables are presented in table 7 (for normal hearing adults) and in table 8
(for moderate-to-severe hearing impaired adults).
The results of moderate-to-severe congenital hearing impaired and normal
hearing adults on MLU and the MLUL were compared. There were no significant
differences in performance between the two groups on these measures. [MannWhitney U = 88.000 for MLU and 87.500 for MLUL; NH= 10, MSCHI= 20; p>0.05].
Although for Dutch no data are available regarding Mean Length of the (longest)
Uterrance(s) in adults, the results found in this research were similar to those found
by Nippold (2005, table 1, p.1053) for English, normal hearing adults. Research
question 1.a is thus answered: adults with congenital moderate-to-severe hearing
loss do not produce shorter sentences than normal hearing impaired.
Table 7. Descriptive statistics on measures of language production for expository discourse
for normal hearing adults.
NH
ML T-unit
MLU5L
(N=10)
Clausal
Relative
Adverbial
Nominal
Density
CD
CD
CD
(CD)
Mean
10,0250
25,6800
1,3690
1,0750
1,1740
1,1210
Median
10,1150
25,2000
1,3900
1,0750
1,1600
1,1300
1,30343
5,32933
,11318
,06721
,05739
,05087
Std.
Deviation
44
Table 8. Descriptive statistics on measures of language production for expository discourse
for moderate-to-severe hearing impaired adults
MSCHI
ML T-unit
MLU5L
(N=20)
Clausal
Relative
Adverbial
Nominal
Density
CD
CD
CD
(CD)
Mean
10,3185
23,6600
1,3910
1,0725
1,1840
1,1350
Median
10,2450
23,0000
1,3900
1,0600
1,1400
1,1000
1,63059
3,87548
,16638
,06988
,11417
,11335
7,07
16,40
,62
,30
,44
,40
Std.
Deviation
Range
For all complexity variables the Mann-Whitney U test was used assessing
whether or not the samples from normal hearing and moderate-to-severe hearing
impaired adults had different values on the most important variables for syntactic
complexity. Overall the expectation was that moderate-to-severe adults would use
syntactically less complex language and therefore would produce less of all types of
complex clauses. Their scores on all complexity variables were expected to be lower
compared the adults with normal hearing. Because the hypotheses (see section 2.4)
were directional and obviously had one expectation it was suitable to look at the ttest only one-tailed. The data in table 9 show that on none of the complexity
variables a significant difference was found [Mann Whitney U = range 83,500 to
98,500; NH=10, MSCHI=20; p<0.05] between the performance of normal hearing
and moderate-to-severe congenital hearing impaired adults.
Table 9
Results on the Mann Witney U test for complexity variables for normal hearing and
moderate-to-severe hearing impaired adults.
MannWhitney U
Z
Exact Sig.
(2-tailed)
Sig. (1-tailed)
%nom
%adv
%rel
%
Clausal
Relative
Adverbi
Nominal
cl
cl
cl
Direct
density
CD
alCD
CD
speech
(CD)
91,500
98,500
96,500
90,000
94,500
97,500
89,000
83,500
-,374
-,066
-,154
-,451
-,242
-,110
-,485
-,728
,721
,957
,888
,665
,820
,922
,641
,480
,361
,478
,444
,334
,410
,461
,320
,240
45
The density variables for syntactic complexity showed no significant differences
between the two groups. These findings provide answers to research questions 1.a to
e. Moderate-to-severe congenital hearing impaired adults do not have lower clausal
densities than adults with normal hearing. Because differences in clausal density
variables for both groups are not significantly different, it can be concluded that
relative clausal density is not a significantly better measure for complexity than
clausal density.
4.2 Results for error analysis
The results for subordinate sentence grammaticality (analyzed for morphosyntactic error inside and outside the subordinate structure of the sentence, see
section 3.3.2) are presented in this section. Table 10 shows the measures for
subordinate clause grammaticality for adults with normal hearing, where table 11
shows the results for moderate-to-severe hearing impaired adults.
Table 10 Results for subordinate clause grammaticality for adults with normal hearing.
NH (N=10)
% Ungrammatical
% Error outside
% Error inside
subordinate clause
subordinate clause
subordinate clause
structure
structure
Mean
4,1014
1,6071
2,4943
Median
1,6667
,0000
,0000
7,62412
3,98854
4,05026
Std. Deviation
NH (N=10)
% Wrong
%
% Wrong
%
pronoun
Pronoun
complementizer
Complementizer
deletion
deletion
Mean
,3846
2,5507
,0000
1,2500
,0000
Median
,0000
,0000
,0000
,0000
,0000
1,21626
4,75777
,00000
3,95285
,00000
Std. Deviation
% V2
46
Table 11 Results for subordinate clause grammaticality for moderate-to-severe congenital
hearing impaired adults.
MSCHI (N=20)
% Ungrammatical
% Error outside
% Error inside
subordinate clause
subordinate clause
subordinate clause
structure
structure
Mean
15,2043
13,7511
5,0038
Median
11,6516
7,7381
3,3482
15,42249
19,37362
6,20377
Std. Deviation
MSCHI (N=20)
% Wrong
%
% Wrong
%
pronoun
Pronoun
complementizer
Complementizer
deletion
Mean
deletion
1,2319
,6401
1,3298
,1282
1,6738
,0000
,0000
,0000
,0000
,0000
2,45710
1,71033
2,79171
,57335
2,74402
Median
Std. Deviation
% V2
Table 10 directly shows no results on wrong complementizer and V2, meaning
that normal hearing adults made no errors in these categories. Hearing impaired
adults made mistakes in all five error categories. To see if there were significant
differences in the grammaticality of the produced subordinated clause, statistical
analysis on the morpho-syntactic errors was performed.
Results (see table 12) show that there is a significant difference in the amount of
ungrammatical subordinate sentences. Hearing impaired adults produced more
ungrammatical subordinate clauses than the normal hearing control group [Mann
Whitney U = 85,500 N1=10 N2=20; p>0.05]. It should be noted that this involves
all sorts of errors both inside and outside the clause structure. Isolated, the variable
‘errors outside the subordinate clause structure’ does also show a significant
difference [Mann Whitney U = 55,000, P<0,05], where the category ‘errors inside
the subordinate clause structure’ does not show a significant difference [Mann
Whitney U = 75,000, p>0.05]. Based on these findings it can be concluded that
hearing impaired adults do make more errors in complex clause structures than
normal hearing adults. This answers research question 2 and provides evidence to
accept hypothesis 4.
47
Table 12 Results on the Mann Witney U test for subordinate clause grammaticality and
morpho-syntactic errors for normal hearing and moderate-to-severe hearing impaired adults.
% Ungrammatical
% Error outside
subordinate clause
% Error inside
subordinate clause subordinate clause
structure
structure
Mann-Whitney U
40,000
55,000
75,000
Wilcoxon W
95,000
110,000
130,000
Z
-2,666
-2,149
-1,160
Exact Sig. (2-tailed)
,006
,031
,256
Exact Sig. (1-tailed)
,003
,014
,128
%
%
% Wrong
%
Wrong
Pronoun
complemen-
Complementizer
pronoun
deletion
tizer
deletion
Mann-Whitney U
% V2
85,500
85,000
92,000
95,000
87,000
140,500
140,000
147,000
150,000
142,000
-,913
-1,267
-,542
-,707
-,735
Exact Sig. (2-tailed)
,465
,458
,640
1,000
,445
ExacSig. (1-tailed)
,239
,281
,449
,667
,218
Wilcoxon W
Z
4.3 Results for avoidance strategies
Analysis of unambiguous avoidance strategies (see section, 3.3.3) only led to
one category where numbers were large enough for statistical analysis. Both hearing
impaired and normal hearing produced direct speeches. Although the average rate
was slightly higher for hearing impaired adults (see table 13), a Man Whitney U test
showed no significant difference between both groups (see table 14).
Table 13 Results for direct speech for adults with hearing impaired adults and adults w
normal hearing
MSCHI (N=20)
%
Direct speech
NH (N=10)
%
Direct speech
Mean
2,4870
Mean
3,2700
Median
1,8850
Median
2,9850
Std. Deviation
Std. Deviation
2,77277
3,63128
48
Table 14 Results on the Mann Witney U test for direct speech for normal hearing and
moderate-to-severe hearing impaired adults.
% direct speech
Mann-Whitney U
110,000
Z
-0,42
Exact Sig. (2-tailed)
,3372
Exact Sig. (1-tailed)
,06745
Some examples of verb first were observed in spontaneous speech samples of
moderate-to-severe hearing impaired adults (occurring in 3 out of 10 samples) as
well as in normal hearing adults (4 out of 20 sample). As said, number were small,
except for a peak at one of the hearing impaired adults who produced 7 verb first
sentences on a total number of 72 T-unit. Clausal conjunction was only observed in
one sample of a hearing impaired adult. From this can be concluded that hearing
impaired adults do not make (more) use of avoidance strategies than normal hearing
adults. This forms the answer to research question 3.
5. Conclusion and discussion
The aim of the research, executed in this thesis, was to provide answers to the
research questions and hypotheses as formulated in section 2.4, which were formed
based on the literature study in chapters 1 and 2. Answers were found by analyzing
the spontaneous speech samples of 20 moderate-to-severe congenital hearing
impaired adults and 10 normal hearing adults, that were obtained by eliciting
expository discourse.
No significant differences in appearance of complex clause structures in
spontaneous speech sample between moderate-to-severe hearing impaired and
normal hearing adults were observed. The language of all participating subjects,
normal hearing and hearing impaired) comparable with the findings of Nippold (2005
and 2007 for normal hearing adolescents and adults), is characterized by complex
syntax, using all syntactic structures and the ability to combine structures into longer
sentences and (multi-) subordinate clauses. Moderate-to-severe congenital hearing
impaired adults produced comparable amounts of nominal, adverbial and relative
clauses, so that no difference in clausal densities was observed between both groups.
This indicates that the language of moderate-to-severe hearing impaired adults is
49
not less syntactically complex than the language of the normal hearing adults.
Hypotheses 1 and 2 on the basis of these findings must be rejected.
A possible explanation for the equal performance on syntactic complexity could
be that Dutch hearing impaired adults do not or no longer experience problems on
syntactic complexity. Another plausible explanation could be the fact that the
moderate-to-severe congenital hearing impaired were on average higher educated
than the normal hearing controls. Higher education could indicate that the
moderate-to-severe congenital hearing impaired group had a higher intelligence
which could implicate that they have a more sophisticated ability to create complex
language, including higher causal densities. The relation between intelligence and
syntactic complexity in (normal hearing) adults could be a potential topic for further
research.
The small group sizes could also be a possible explanation, making statistical
data less representative. The same counts for the sample sizes. In addition, the
samples varied widely in size; some subjects producing less than 30 utterances.
Although almost all types of complex sentences occurred in all samples, the small
sample sizes could have negatively affected the statistical results. It would be
interesting to do a similar study with a larger test group and by setting a minimum
of 100 T-units (Marinellie, 2004) as an exclusion criterion.
Regardless of the methodological aspects of the research another explanation
for the observed findings could be found in the linguistic proficiency of the subjects
as a result of a completed maturation. Clausal density and especially relative clause
production are two indicators for syntactic complexity that are sensitive to growth
(Nippold (2005, 2009). Because of the language being fully mature for adult subjects
there may be no difference in use of complex sentences between moderate-tosevere hearing impaired and normal hearing adults. The would argue for
normalisation of language in the moderate-to-severe hearing impaired subjects
participating in this study, which is contrary to the findings of Delage and Tuller
(2007).
However, that language does not normalize with age can be demonstrated by
the significant difference for number of errors made in subordinate clauses between
moderate-to-severe hearing impaired and normal hearing adults; all types of ‘errors
inside the subordinate clause structure’, merged as one variable, and the variable
‘errors outside the subordinate clause structure’ together demonstrated a
significantly different between both groups. Moderate-to-severe hearing impaired
adults do make more errors in complex syntax than their normal hearing peers,
50
which supports hypothesis 4. ‘Errors outside the subordinate clause structure’ within
this thesis are not further specified in this research, but a quick look at the data does
show that errors do occur in the unstressed morphemes, components likely to be
missed by hearing impaired children acquiring language. The most common mistakes
are made in verb inflections (for example hij komø / ‘he comeø’) and using the
wrong determiner or omitting a determiner (gedurende ø hele wedstrijd / during ø
whole game). These results are similar to those of Elfenbein (1994). The findings
suggest that language of the subjects participating in study in the participating did
not normalize with age as they still have problems with morpho-syntax / grammar.
To provide an answer to the question if more errors do occur in syntactically
complex sentences (subordinate clauses) than in syntactically less complex
sentences (as simple main clauses and coordinate clauses) it is necessary to know
how many ungrammatical (categorized) main clauses were produced by the subjects.
These data for this study were unfortunately not (yet) available, but will be published
soon (Huysmans, et al. to appear). In the future it would be very valuable to
combine the research results of these studies. This could possibly lead to new
insights on the relation between morpho-syntactic errors and syntactic complexity.
The compensatory strategies that moderate-to-severe hearing impaired adults
would possibly use in their spontaneous speech formed a complicated category
within thesis. Compensatory strategies have not been extensively studied nor clearly
described. In this thesis it was tried to form some unambiguous categories of
avoidance strategies. It was hypothesized that moderate-to-severe hearing impaired
adults would use more avoidance strategies than normal hearing adults. This does
not seem to be the case. Although the amounts of examples per avoidance variable
were too small for statistical analysis, all kinds of avoidance patterns (e.g. direct
speech, verb first) were observed in moderate-to-severe hearing impaired adults and
less or not in normal hearing adults. Since hearing impaired adults still have
problems with the production of grammatically correct complex sentences,
(demonstrated by the significant difference in errors between normal hearing and
hearing impaired adults) it seems likely that they would try to avoid complex syntax.
Using syntactically less complex sentences would probably decrease the number of
errors in spontaneous language production. Future research on avoidance strategies
in hearing impaired children and adults could be interesting. However, the
expectation is that a large database with a representative amount of examples of
avoiding is needed in order to be able to define and describe different types of
avoidance.
51
6.
Bibliography
Armon-Lotem, S. (2005) The acquisition of subordination: From preconjunctionals to
later use. In: Dorit Ravid and Hava Bat-Zeev Shyldkrot (eds.) Perspectives on
language and language development. New York: Kluwer Academic Publishers,
192-204
Bamford, J., and E. Saunders. (1999) Hearing impairment, auditory perception and
language disability. London: Whurr Publishers
Bench, J., and J. Bamford (1979) The design and construction of sentences for
speech-hearing assessment; background to the study. In: Speech-hearing
tests and the spoken language of hearing-impaired children. Bench, J., and J.
Bamford (ed.), London / New York: Academic Press, 3-25
Blamey, P. J., J. Z. Sarant, et al. (2001) Relationships among speech perception,
production, language, hearing loss, and age in children with impaired hearing.
Journal of Speech, Language and Hearing Research 44, 264-85
Bliss, L. S. (2002) Discourse impairments: Assessment and intervention applications.
Boston: Allyn & Bacon.
Bloom, L., K. Lifter, and J. Hafitz (1980) Semantics of verbs and the development of
verb inflection in child language. Language 56, 386-412
Bol, G. and F. Kuiken (1988) Grammaticale analyse van
taalontwikkelingsstoornissen. Ph.D. dissertation University of Amsterdam,
Utrecht: Elinkwijk
Bowerman, M. (1979) The acquisition of complex sentences. Language
acquisition285-306.
Briscoe J., Bishop D. and C. Norbury (2001) Phonological processing, language, and
52
literacy: A comparison of children with mild-to-moderate sensorineural
hearing loss and those with specific language impairment. Journal of Child
Psychology and Psychiatry 42-3, 329–340
Brown, R. (1973) A First Language. The Early Stages. Harmondsworth: Penguin
Education.
Calvert, D.R. (1982) 'Articulation and hearing impairment.' In: Lass, N.J.,
McReynolds, L.V., Northern, J.L and David, E.Y. (ed.) Speech language and
hearing. II Hearing disorders. Philadelphia: B.C. Decker, 638-48
Carnie, A. (2006) Syntax. A generative introduction (II edition). Oxford, England:
Blackwell
Chomsky, N. (2001) Beyond explanatory adequacy. Cambridge, MA: MIT press. Clark, J. G. (1981). Uses and abuses of hearing loss classification. Asha, 23, 493–
500.
Davis, J.M. Efenbein, J. Schum, R. and R.A. Bentler (1986) 'Effect of mild and
moderate hearing impairments on language, education and psychological
behaviour of children.' Journal of speech and Hearing Disorders 51, 53-62
Delage, H., and L. Tuller (2007) Language development and mild-to-moderate
hearing loss: does language normalize with age? Journal of Speech, Language
and Hearing Research 50, 1300-13
Delage, H., Monjauze, C., Hamann, C. and L. Tuller (2008) Relative clauses in
atypical acquisition of french. In: Language Acquisition and Development:
Proceedings of GALA 2007, Barcelona, Gavarró, A., andJ. Freitas (ed.),
Newcastle: Cambrigde Scholars Publishing, 166-76
Delage, H. and L. Tuller (2009) Evolution of syntactic complexity and avoidance
strategies in children with mild-to-moderate hearing loss. oral presentation at
GALA, September 2007, Lisbon
Dromi, E., and R. A. Berman. 2008. Language-specific and language-general in
developing syntax. Journal of Child Language 13.371-87.
53
Dungen, L. van der and Verbeek, J. (1999) STAP- Manual. Amsterdam: University
of Amsterdam
Elfenbein, J.L., Hardin-Jones, M.A. and J.M. Davis (1994) Oral communication skills
of children who are hard of hearing. Journal of Speech and Hearing Research,
37-1, 216-226
Friedmann, N., and R. Szterman (2006) Syntactic movement in orally trained
children with hearing impairment. Journal of Deaf Studies and Deaf Education
11, 56-75
Gilbertson M. and A. Kamhi (1995) Novel word learning in children with hearing
impairment. Journal of Speech and Hearing Research 38, 630-642
Gillis, S. and A. Schaerlaekens (2000) Child Language acquisition: a handbook for
Dutch. (Kindertaalverwerving: Een handboek voor het Nederlands) Martinus
Nijhoff, Groningen, Netherlands
Groenestyn, M. (2011) Language performance in adults with moderate to severe
congenital hearing impairment MA-thesis, Utrecht: University of Utrecht
Hamann, C. , Tuller, L. et al. (2007) (Un)successful subordination in Frenchspeaking children and adolescents with SLI. Oral presentation at 'the romance
turn II, sept 2007, Utrecht.
Hunt, K. W. (1970) Syntactic maturity in schoolchildren and adults. Monographs of
the society for research in child development 134-35 nr.1, 1-67
Huysmans, E., J. de Jong, J.H. Van Lanschot-Wery, J.M. Festen & S.T. Goverts
(2011) 'Long-term effects of congenital hearing impairment on language
performance in adults.', to appear.
54
Kuhl, P. K. (2004) Early language acquisition: cracking the speech code. Nature
Reviews Neuroscience, 5, 831-843
Kumaravadivelu, B. (1994) Intake factors and intake processes in adult language
learning. Applied language learning 5, 33-71
Lenneberg, E. H., N. Chomsky, and O. Marx (1967) Biological foundations of
language. New York: Wiley
Loban, W. (1976) Language Development: Kindergarten through Grade Twelve.
NCTE Committee on Research Report 18
Marinellie, S.A. (2004) 'Complex syntax used by school-age children with specific
language impairment (SLI) in child–adult conversation.' Journal of
Communication Disorders 37, p.517–533
McGuckian, M. and A. Henry (2007) 'The grammatical morpheme deficit in moderate
hearing impaired.' International Journal of Language and Communication
Disorders 42, 17-36
Moeller, M., Tomblin, J. et al. (2007) Current state of knowledge: language and
literacy of children with language impairment. Ear and hearing 28-6, 740-753
Mogford, K. (1993) Language acquisition and development with sensory impairment:
hearing-impaired children, 660-79. In: Linguistic disorders and pathologies
Blanken, J., H. Dittman, and H. e. a. Grimm (ed.), Berlin - New York: De
Gruyter
Newport, E. L. (1990) Maturational constraints on language learning. Cognitive
Science: A Multidisciplinary Journal 14, 11-28
Nieminen, L. (2009) MLU and IPSYN measureing absolute complexity Eesti
rakenduslingvistika uhingu aastaraamat, vol. 5 p.173-185
55
Nippold, M. A. (2009) School-age children talk about chess: does knowledge drive
syntactic complexity? Journal of Speech, language and Hearing Research 52,
856-71
Nippold, M. A., L. J. Hesketh, J. K. Duthie, and T. C. Mansfield (2005) Conversational
versus expository discourse: a study of syntactic development in children,
adolescents, and adults. Journal of Speech, language and Hearing Research
48, 1048-64
Nippold, M.A., Mansfield T.C. and J.L. Billow (2007) Peer conflict explanations in
children, adolescents, and adults: examining the development of syntax.
Amarican Journal of Speech-Language Pathology 16, p.179-188
Nippold, M. A., T. C. Mansfield, J. L. Billow, and J. B. Tomblin (2008) Expository
discourse in adolescents with language impairments: examining syntactic
development. Amarican Journal of Speech-Language Pathology 17, 356-66
Nippold, M.A. (2010) Language sampling with adolescents. San Diego: Plural
Publishing
Norbury, C. , D. V. M. Bishop, and J. Briscoe (2001) Production of English finite verb
morphology: a comparison of SLI and mild-moderate hearing impairment.
Journal of Speech, language and Hearing Research 44, 165-78
Penner, Z. (1995) Continuity constraints on paradigm formation in the acquisition of
the complementizer system. A case study in Bernese Swiss German.
Unpublished manuscript, University of Bern, Swisserland.
Penner, Z. and N. Müller (1992). ' On the early stages in the acquisition of finite
subordinate clauses. The syntax of the so-called preconjunctional subordinate
clauses in German, Swiss German, and French.' Geneva Generative Papers
1(2), p.163-181
56
Scott, C.M. (1988)
'Spoken and written syntax.' In: M.A. Nippold (ed.) Later
language development: Ages nine trough nineteen Austin (TX): pre-ed., p.4595
Semel, E., Wiig, E.H, Secord, W.A., Kort, W. (2008) CELF® 4 NL: clinical evaluation
of language fundamentals. (Dutch version) Amsterdam: Pearson
Smith, C. (1988) Factors of linguistic complexity and performance. Linguistic
Complexity and Text Comprehension: Readability Issues Reconsidered.
Hillsdale, NJ: Lawrence Erlbaum Associates
Smith, C., and A. van Kleeck (1986) Linguistic complexity and performance. Journal
of Child Language 13, 389-408
Spencer, P. and M. Marschalk (red.) (2006) Advanced in spoken language
development of deaf and hard-of-hearing children. Oxford: Oxford University
Press
Svirsky, M.A. (2000) Language development in children with profound and
prelingual hearing loss, without cochlear implants. Annuals of Otololgy,
Rhinology and Laryngology Supplement, 99-100 Tuller, L. and Jakubowicz (2004) Developpement de la morphosyntaxe du français
chez des enfants sourds moyens. Le langage et 'homme: logopédie,
psychologie, audiologie 14, 191-207 Tuller, L. , Herny, C. Sizaret, E. and M. Barthez (2012) Specific language
impairment at adolescents: avoiding complexity. Applied Psycholinguistics 33,
161-184
Vandeweghe, W. van (2004) Grammar of the Dutch phrase Antwerpen/ Apeldoorn:
Grarant Uitgevers n.v.
57
Verhoeven, L., M. Aparici, D. et al. (2002) Clause packaging in writing and speech: A
cross-linguistic developmental analysis. Written Language & Literacy 5, 13561
Zwart, J. (2011) The syntax of Dutch. Cambridge: Cambridge Univerisity Press
58
Appendix I: List of abbreviations used in this thesis and appendix II
BPVS =
British Picture Vocabulary Scale
CD =
clausal density
CLAN =
Corpus of Language & Nature
CELF =
Clinical evaluation of Language Fundamentals
CG =
control group
CHI =
congenital hearing impairment
CNrep =
the Children’s Non-word repetition task
Con. D =
conversational discourse
Exp. D =
expository discourse
FGST =
favourite game or sport task
GM =
grammatical morpheme
HI =
hearing impairment
L2 =
second language
MLU =
Mean Length of Utterance (in words)
MLUL =
Mean length of the (5) longest utterances
MMHL =
mild-t-moderate hearing loss
MMSNHL =
mild-to-moderate sensorineural hearing loss
MSCHI =
mild- to-severe congenital hearing impairment
NH =
normal hearing
NLI =
non-specific language impairment
PRCT =
peer conflict resolution task
RE =
Rolandic Epilepsy
SALT =
systematic analysis of language transcripts
SLI =
specific language impaired /impairment
subo. =
subordination
synt. compl.=
syntactic complexity
TD =
typically developed / developing
TL =
typical language
TOLD =
the Grammatical Completion subtest of the Test of Language
development
TROG =
Test for Reception of Grammar
V2 =
verb second
59
Appendix II: Detailed information about the discussed studies
Study
Subjects +
language
Age
Research topic / questions
Task
Results
Delage, Monjauze,
Hamann & Tuller
(2008)
SLI (N=21),
MMHL
(N=21), RE
(N=11), 3
control groups
(3 x N=12)
AD 9;013;0
Is there an age effect in TD
children? Do AD children show
avoidance pattern “pseudo
relatives” at higher rate and at
older ages?
Spontaneous
language
samples analyzed
with CLAN
An age effect was outlined in TD. AD
used less complex structures, avoidance
normal relatives. SLI avoided complex
structures and had the highest error rate.
RE scored like TD on subordination but
like AD for avoidance. MMHL resembles
SLI, but did produce normal relatives
Delage & Tuller
(2007)
MMHL (N=19)
TD (several)
SLI (N=12)
Adolescents
11;0-15;0
Do adolescents with HL display
late normalization?
- BILO
- naming task
- sentence
completion task
- reading timed
task
- word
identification task
- lexical
judgement task
- grammatical
judgement task
Language disorders in areas of phonology
and grammar. No normalization with age
in MMHL. Effect of severity of HL only
after childhood
Analysis of
spontaneous
language
samples
approximately 60
utterances per
subject, using
CLAN,
Participants with MMHL tended to avoid
finite embedded clauses and genuine
relatives. Moreover, they produced failed
attempts at embedding much more
frequently than controls. Finally, when
they produced complex utterances, they
produced a great number of errors,
especially in the most complex embedded
clauses, i.e. in relative clauses.
Control
groups of
6;0, 8;0
and 11;0
Are there similarities (qual./
quan.) between MMHL and SLI
language disorders in
adolescents?
(French)
Delage & Tuller
(2009)
N=32
adolescents
with MMHL
(French)
two age
groups:
N1=16
aged 6 to 9
N2=16
aged 9 to
11
Focuses on the evolution of
syntactic complexity and the use
of avoidance strategies in a
population of children and
adolescents with mild-tomoderate hearing loss (MMHL)
60
Study
Subjects +
language
Age
Research topic / questions
Task
Results
Elfenbein, HardinJones & Davis (1994)
MSCHI
(N=40)
5;0 – 18;0
Describe oral communication
skills of MSCHI children and
adolescents
- Test of
articulation
competence
- Grammatical
completion task
- Interview
MSCHI showed phonological problems
and made syntactic errors. Their
pragmatic errors consisted primarily of
providing inadequate or ambiguous
information to the listener.
Spontaneous
speech, language
battery, cognitive
battery
Children with SLI produce less complex
clauses than TD and much higher rate of
these are ungrammatical. Adolescents did
not produce significantly more
subordination than children, suggesting
that rates of embedding stagnate. The
rate of ungrammatical utterances
decreased, though not significant.
Percentages of avoidance strategies
(shallower embedding, direct speech) do
not decrease with age in SLI, as they do
in TD.
Long-term effects of MSCHI in
the domain of morpho-syntax;
do MSCHI have a lower level of
performance compared to NH
adults?
CELF-4 nl
FGST
Data show long term-effects of MSCHI in
morpho-syntax. CELF-scores did not
reveal any group differences.
How moderate HI impacts on the
use of GM’s in speech and to
provide an explanation for
pattern of findings
Spontaneous
speech, analyzed
to determine the
use of GM’s
CG (N=16)
MSCHI language skills compared
to NH along a continuum
Hamann, Tuller,
Monjauze, Delage &
Henry (2007)
SLI
children N=10
and
adolescents
N=18
children =
5;10 10;5
adolescents
= 10;1115;7
Do children and adolescents with
SLI have problems with
computational complexity?
Prediction: subordination will be
difficult and will manifest itself
with high error rates.
TD controls
(French)
Huysmans, E., Jong,
J. de, Lanschot-Wery
J.H. van, Festen J.M.
& S.T. Goverts (to
appear)
MSCHI
(N=20)
NH (N=10)
McGuckian & Henry
(2007)
HI and and TD
MLU matched
control group
(Dutch)
(English)
3 control
groups: age
6 / 8 /11
NH = 20;0
– 34;0
MSCHI =
20;0 – 45;0
Analysed by
measures from
STAP, completed
with error
categories, CD
and CD for subo.
Significant difference between HI and TD
for 5 GM’s. No significant difference in
accuracy order was found. Accuracy
order of HI was characteristic of that of
L2.
61
Study
Subjects +
language
Age
Research topic / questions
Task
Results
Marinellie, S.A.(2004)
SLI (N= 15)
Mean age
SLI 10;8
Differences between TL and SLI
in syntactic complexity in
ordinary language samples
Spontaneous
speech in
conversational
discourse.
Concerns about the validity of
conversational discourse for language
sampling for syntactic complexity. SLI
less complex than TL.
TD (N=15)
(Am. English)
Mean age
TD 10;0
Transcribed using
SALT
Nippold, M.A. (2009)
32 children
playing chess.
Mean age
10;11
Do different topics influence
synt. compl.
(English)
3 conversation
types:
-general
- chess conv.
- chess
explanation
Total T-units, ML, CD and use of subo.
were higher in chess explanation than in
general - and chess conversation.
Chess knowledge was of no influence on
language performance for any type of
conversation.
transcripts were
analyzed for:
ML/ T-unit, CD,
subo. clause use.
Nippold, M. A., L. J.
Hesketh, J. K. Duthie,
and T. C. Mansfield
(2005)
TD (N = 120)
in 6 groups of
20 subjects.
(English)
6 groups
with mean
ages: 8;1,
11;4, 13;9,
17;3, 25;6,
44;8
How does synt. dev. Differ in
Con.D vs Exp.D?
What markers for synt. growth
exist in Con. D and Exp. D?
Con. D about
common topics
vs. Exp. D
elicited by a
FGST
Best indicators for synt. growth are ML/Tunit and rel. CD, with age relatedincrease into early adulthood. Total
number of T-units increased with age.
Large individual differences!
- PCRT
- FGST
Older packed more info in their speech
than younger speakers. PCR elicited more
Exp. D than FGS.
Changes in synt. dev. occur
during adulthood.
Levels of performance?
Nippold, M.A.,
Mansfield T.C. and
J.L. Billow (2007)
TD (N=60)
(English)
11;0, 17;0
and 25;0
Synt. compl. in Exp. D
62
Study
Subjects +
language
Age
Research topic / questions
Task
Results
Nippold, M. A., T. C.
Mansfield, J. L.
Billow, and J. B.
Tomblin (2008)
SLI (N=106)
NLI (N=84)
TLD (N=254)
Mean
(controlled)
age 13;11
Better use of syntax in NLI and
SLI in expository over
conversational discourse?
- CELF
- Language
samples in Con.
D and Exp.D
analyzed for ML/
T-unit + subo.
clause production
MLU /T-unit and subo. use were greater
during Exp.D for all groups. TLD
outperformed NLI and SLI for MLU/ Tunit and NLI for relative clause
production.
Comparison between the
performance of finite verb
morphology of MMSNHL and SLI
- BPVS
- TROG
- recalling
sentence subtest
of the CELF
- CNrep
- Finite Verb
Morphology Task
- Past Tense
Elicitation
Degree of hearing loss was not directly
related to performance. Acquisition of
finite verb morphology may be delayed in
children with hearing impairment.
Children with SLI produce unmarked
stems in context where the inflection is
obligatory more often.
Would language sampling reveal
syntactic deficits in NLI and SLI?
(Am. English)
Norbury, Bishop, &
Briscoe (2001)
MMSNHL
(N=19)
CG (N=20)
SLI (N=14)
CG (n=15)
MMSNHL
+CG age
5;9-10;7
SLI +CG
age 7;210;9
Schick (1997)
Profoundly
deaf (N=13)
(English)
7;1 - 14;8
Effects of discourse genre on
complexity
Spontaneous
speech, narrative
elicitation,
interview through
challenging
questions.
The most complex language was
produced during the interview, measured
by embedded clauses, conjunctions and
modals. Utterance length did not vary as
a function of sample type.
Tuller, Henry, Sizaret
& Barthez (2012)
SLI, syntax,
complexity,
adolescents,
avoidance
N=18 SLI +
control
group
Complex language in adolescents
with SLI ; characteristic of
typical syntactic development
after childhood
Spontaneous
language
samples
Complexity increases with age in TD,
behaviours of avoidance are clear in the
SLI, in the form of low frequencies of
complex structures, but also frequency of
failed attempts and alternative
strategies.Whereas increasing complexity
is the hallmark of syntactic development
after childhood, avoidance of complexity
appears to characterize SLI after
childhood.
(French)
Do individuals with SLI avoid
using structures whose syntactic
derivation involves greater
computational complexity?
63
Appendix III: Research data
name
NH01
NH02
NH03
NH04
NH05
NH06
NH07
NH08
NH09
NH10
SH01
SH02
SH03
SH04
SH05
SH06
SH07
SH08
SH09
SH10
SH11
SH12
SH13
SH14
SH15
SH16
SH17
SH18
SH19
SH20
total number
total number of analyzed
5 longest
cl.
T-units
number T-units ML of t-unit
T-unit
104,00
76,00
76,00
9,95
91,00
61,00
61,00
11,57
94,00
72,00
72,00
8,63
82,00
58,00
58,00
10,28
81,00
55,00
55,00
11,35
91,00
73,00
73,00
8,79
113,00
75,00
75,00
11,72
55,00
47,00
47,00
8,60
67,00
47,00
47,00
10,79
78,00
61,00
61,00
8,57
55,00
43,00
43,00
11,72
221,00
182,00
100,00
10,03
79,00
47,00
47,00
12,85
102,00
72,00
72,00
11,01
46,00
30,00
30,00
10,63
79,00
55,00
55,00
11,35
49,00
34,00
34,00
10,71
233,00
211,00
100,00
8,63
58,00
40,00
40,00
11,25
76,00
58,00
58,00
9,79
129,00
117,00
100,00
8,63
92,00
66,00
66,00
10,35
100,00
72,00
72,00
12,19
100,00
66,00
66,00
10,14
41,00
26,00
26,00
9,88
76,00
59,00
59,00
9,66
40,00
23,00
23,00
13,13
41,00
36,00
36,00
6,06
74,00
61,00
61,00
9,74
189,00
161,00
100,00
8,62
ML of
26,80
38,00
23,60
20,40
27,40
21,00
28,60
22,60
27,60
20,80
29,40
26,40
27,80
26,80
24,60
27,00
20,80
22,20
21,60
23,60
21,20
24,00
29,00
22,20
19,80
22,20
27,80
13,00
21,40
22,40
coordination
subordination
48,00
28,00
39,00
30,00
23,00
22,00
23,00
24,00
21,00
26,00
48,00
18,00
46,00
38,00
16,00
8,00
30,00
20,00
16,00
17,00
29,00
12,00
31,00
39,00
30,00
32,00
36,00
30,00
17,00
16,00
41,00
24,00
13,00
15,00
35,00
22,00
9,00
18,00
21,00
18,00
44,00
12,00
30,00
26,00
63,00
28,00
37,00
34,00
15,00
15,00
33,00
17,00
14,00
17,00
14,00
5,00
30,00
13,00
57,00
28,00
64
name
NH01
NH02
NH03
NH04
NH05
NH06
NH07
NH08
NH09
NH10
SH01
SH02
SH03
SH04
SH05
SH06
SH07
SH08
SH09
SH10
SH11
SH12
SH13
SH14
SH15
SH16
SH17
SH18
SH19
SH20
%nom
%adv
14,29
40,00
40,91
37,50
38,46
27,78
26,32
37,50
30,00
35,29
41,67
33,33
43,75
13,33
6,25
62,50
26,67
22,73
22,22
27,78
33,33
30,77
53,57
64,71
6,67
23,53
58,82
20,00
46,15
21,43
%rel
85,71
33,33
54,55
33,33
30,77
55,56
39,47
62,50
45,00
58,82
33,33
58,97
12,50
73,33
87,50
25,00
46,67
45,45
61,11
61,11
25,00
30,77
28,57
11,76
66,67
70,59
41,18
80,00
53,85
57,14
CD %
0,00
26,67
4,55
29,17
30,77
16,67
34,21
0,00
25,00
5,88
25,00
7,69
43,75
13,33
6,25
12,50
26,67
31,82
16,67
11,11
41,67
38,46
17,86
23,53
26,67
5,88
0,00
0,00
0,00
21,43
rel. CD
1,37
1,49
1,31
1,41
1,47
1,25
1,51
1,17
1,43
1,28
1,28
1,39
1,68
1,42
1,53
1,44
1,44
1,22
1,45
1,31
1,12
1,39
1,39
1,52
1,58
1,29
1,74
1,14
1,21
1,28
adv. CD
1,00
1,13
1,01
1,12
1,15
1,04
1,17
1,00
1,11
1,02
1,07
1,03
1,30
1,06
1,03
1,05
1,12
1,07
1,08
1,03
1,05
1,15
1,07
1,11
1,15
1,02
1,00
1,00
1,00
1,06
nom. CD
1,32
1,16
1,17
1,14
1,15
1,14
1,20
1,11
1,19
1,16
1,09
1,23
1,09
1,31
1,47
1,11
1,21
1,10
1,28
1,19
1,03
1,12
1,11
1,08
1,38
1,20
1,30
1,11
1,11
1,16
1,05
1,20
1,13
1,16
1,18
1,07
1,13
1,06
1,13
1,10
1,12
1,13
1,30
1,06
1,03
1,27
1,12
1,05
1,10
1,09
1,04
1,12
1,21
1,33
1,04
1,07
1,43
1,03
1,10
1,06
65
name
NH01
NH02
NH03
NH04
NH05
NH06
NH07
NH08
NH09
NH10
SH01
SH02
SH03
SH04
SH05
SH06
SH07
SH08
SH09
SH10
SH11
SH12
SH13
SH14
SH15
SH16
SH17
SH18
SH19
SH20
%
% errors
% errors
ungram.sub.
outside sub.
inside sub. cl.
% wrong
% compl
cl.
cl. structure
structure
%wrong pro
%pro. del
compl.
deletion
%V2
3,57
3,57
0
0
0
0
0
0
3,33
0
3,33
0
0
0
0
3,333333333
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
3,85
0
3,85
3,846153846
0
0
0
0
0
0
0
0
0
0
0
0
5,26
0
5,26
0
0
0
0
5,263157895
25
12,5
12,5
0
0
12,5
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16,67
16,67
0
0
0
0
0
0
56,41
53,85
17,95
0
2,564102564
7,692307692
2,564102564
5,128205128
6,25
3,125
3,125
3,125
0
0
0
0
0
0
0
0
0
0
0
0
6,25
0
6,25
0
0
0
0
6,25
12,5
8,33
4,17
0
0
0
0
4,166666667
20
0
20
6,666666667
6,666666667
0
0
6,666666667
4,55
0
4,55
0
0
4,545454545
0
0
11,11
11,11
0
0
0
0
0
0
0
0
0
0
0
0
0
0
8,33
0
8,33
8,333333333
0
0
0
0
11,54
11,54
0
0
0
0
0
0
3,57
0
3,57
3,571428571
0
0
0
0
14,71
11,76
2,94
2,941176471
0
0
0
0
20
20
6,67
0
0
6,666666667
0
0
0
0
0
0
0
0
0
0
11,76
17,65
0
0
0
0
0
0
40
60
0
0
0
0
0
0
46,15
53,85
15,38
0
0
7,692307692
0
7,692307692
14,29
7,14
7,14
0
3,571428571
0
0
3,571428571
66
name
NH01
NH02
NH03
NH04
NH05
NH06
NH07
NH08
NH09
NH10
SH01
SH02
SH03
SH04
SH05
SH06
SH07
SH08
SH09
SH10
SH11
SH12
SH13
SH14
SH15
SH16
SH17
SH18
SH19
SH20
%PV1
0
0
0
0
0
11,11111111
2,631578947
0
0
11,76470588
0
0
0
23,33333333
0
0
0
0
0
0
0
0
0
2,941176471
0
5,882352941
0
0
0
0
% direct
speech
0,00
1,64
5,56
0,00
0,00
0,00
8,00
4,26
2,13
3,28
13,95
1,00
4,26
1,39
0,00
0,00
2,94
4,00
0,00
6,90
5,00
4,55
5,56
3,03
0,00
8,47
4,35
0,00
0,00
0,00
67