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Psycholinguistics
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Psycholinguistics
• CHIMP STUDIES
• A number of projects have investigated whether other
primates (especially chimpanzees) can acquire
language if properly taught.
• Positive evidence would have important implications
for nativist theories of language acquisition by humans.
• If chimps can be shown to recognize semantic
categories like FOOD and to apply syntactic patterns
(e.g. word order), then it might suggest that they too
have access to the basic principles underlying
language.
Psycholinguistics
• This would lend itself to one of three
interpretations:
• Chimps share the human language mechanism in
some form, but lack a genetically transmitted
trigger which sets it off as part of maturation.
• There is no innate mechanism peculiar to human
beings: acquiring a language depends upon the
input a child receives.
• Language maps on to established cognitive
operations which human beings share with other
primates.
Psycholinguistics
• Chimps do not have an appropriate vocal apparatus to produce the
sounds of human speech.
• Early attempts were therefore made to teach them a modified
form of the sign language used by the deaf.
• One (Washoe) mastered 130 signs in three years – a rate of
acquisition much slower than that of a human infant.
• Washoe managed to produce sequences of two or three signs,
including some original combinations; but never developed a
consistent word order.
• Another chimp (Nim Chimpsky) managed strings of up to four
signs; and produced an impressive variety of sequences.
• However, Nim’s productions involved much repetition of the same
items and, like those of Washoe, showed great inconsistency of
Subject-Verb-Object word order.
Psycholinguistics
• More recently, researchers have trained chimps to communicate by
indicating lexigrams, simple abstract shapes in various colours.
• Each shape is associated with a word such as JUICE or BANANA, but
they bear no resemblance to the objects they refer to.
• The lexigrams appear on large keys mounted on a computer screen
in the chimpanzee’s cage.
• One chimp, Lana, learned over 100 of these symbols.
• Two others, Austin and Sherman, were taught only a few and were
then rewarded for semantically correct combinations (EAT þ
BANANA rather than DRINK þ BANANA).
• After thousands of trials, they came to recognize these
combinations and (importantly) proved quick to categorize new
items of food and drink when they learnt them.
Psycholinguistics
• One of the most successful results has been achieved with a
bonobo (or pygmy chimpanzee) called Kanzi.
• He was originally present at the training sessions of his foster
mother, Matata.
• When the researchers felt that he was old enough to begin
learning, he showed that he already knew much of what they
wanted to teach him.
• He mastered combinations of lexigrams without the thousands of
trials that Austin and Sherman had needed. In all, he learnt about
400 symbols.
• More importantly, he could group them in lexical sets and showed
signs of using a consistent word order.
• He could understand some simple spoken English, and could
respond appropriately to commands such as ‘Put the soap on the
apple’.
Psycholinguistics
• Kanzi’s relative success has suggested that chimp training should
begin earlier.
• Deacon (1997) links the Kanzi findings to the ‘less is more’ view of
language acquisition, which suggests that at a certain point children
are particularly sensitive to the symbolic nature of a system such as
language precisely because they have not yet fully developed
cognitively.
• However, it is not clear whether Kanzi can be said to have acquired
a form of ‘language’ which resembles the human one in structure
or complexity.
• It may be that the whole concept of chimp training is misleading
because it aims to teach a form of communication that is a
quintessential product of the human mind.
Psycholinguistics
• CHOMSKYAN THEORY
• Noam Chomsky (b.1928) formulated what is currently the
leading model of language, generative grammar.
• His goal was to create a set of rules to account for the
creativity of language: the way in which a potentially
infinite number of sentences can be generated from a finite
set of words.
• A Chomskyan grammar offers a symbolic representation of
the system which native speaker-hearers internalize in
acquiring the language, a system which enables them to
formulate or to understand sentences that they may never
have said or heard before.
Psycholinguistics
• The grammar is generative in that its rules
serve to specify all possible sentences which
are grammatically correct and to exclude from
consideration all those which are not.
• These ‘rules’ are not the prescriptive rules of
traditional grammar.
• They are more like the laws of physics, which
account for disparate natural phenomena in
terms of general underlying principles.
Psycholinguistics
• Chomksyan theory highlights the fact that language is
structure dependent, and provides models of standard
phrase types.
• These are taken to represent the underlying form of an
utterance, its deep structure.
• In the first version of the theory, a set of
transformational rules showed how the user might
reorganize the constituents of a deep structure string
to produce a surface structure one.
• For example, they showed, in stages, how a speaker
derived a passive sentence from an underlying active
form.
Psycholinguistics
• Current theory has replaced the cumbersome transformational
rules with movement rules.
• These show diagrammatically how the deep structure (now dstructure) constituents are moved to new slots to provide a derived
s-structure pattern.
• See how a wh- question is derived from the d-structure string Sara
is reading what.
• An important feature of this revised theory, sometimes referred to
as government and binding, is that when a constituent is moved it
leaves behind a trace (t).
• This enables the listener to retrieve the original deep structure from
the sentence that is heard. Studies in psycholinguistics have
attempted to verify the existence and effect of such traces.
Psycholinguistics
• Chomskyan theory has recently taken a new direction,
known as minimalism, which emphasises the
importance of simplicity in formulating syntactic rules.
• One development is that much of what is traditionally
represented as syntax can be explained by reference to
the constraints which are imposed by lexis.
• Thus, if one decides to construct a sentence around the
verb GIVE, the choice of verb determines the possible
structure VP þ NP þ NP (Elizabeth gave Philip a book).
• This information is stored as part of the lexical entry for
GIVE in the user’s lexicon.
Psycholinguistics
• Chomskyan theory provided a boost for cognitive psychology.
• It moved the discussion on from the simplified accounts provided by
behaviourism; and redirected attention to the mental processes involved
in the production and understanding of language, processes which
behaviourism regarded as inaccessible or non-existent.
• Chomsky made an important distinction between competence, the set of
principles which enable a native speaker to generate an infinite set of
grammatically acceptable sentences and performance, the spoken/
written language to which the system gives rise.
•
This differs somewhat from de Saussure’s distinction between langue and
parole.
• Where de Saussure defines ‘langue’ in relation to the speech community
which shares the language in question, Chomsky relates competence to
the individual user of the language.
Psycholinguistics
• Chomsky argues that linguistic theory needs to be based
upon competence, not performance.
• The goal of the linguist should be to specify the means by
which the native speaker-hearer constructs grammatically
correct sentences rather than to analyze what he/she
actually says.
• Generative grammar thus assumes an ideal speaker-hearer,
one from whose speech idiolectal, dialectal and
hesitational features have been removed.
• It is here that linguistic approaches and psychological ones
diverge, since the data upon which a psychologist
traditionally works is provided by examples of human
behaviour in performance.
Psycholinguistics
• In psycholinguistics, those who work within the
Chomskyan tradition follow a theory-driven approach
which seeks evidence of the psychological reality of
Chomsky’s constructs.
• However, they face a problem in attempting to tap into
competence rather than relying on performance data.
• A solution adopted by many researchers is to ask
subjects to make grammaticality judgements.
• They might, for example, be asked to decide if a
sentence such as Who did you introduce the man you
got the present from to? is grammatically acceptable.
Psycholinguistics
• A second complication is that Chomsky’s grammar is
specifically a model of language.
• Chomsky has much to say on the human mind; but he does
not claim that phrase structure and movement rules
represent the actual process taking place within the mind
of the user as he/she constructs a sentence.
• Hence there is discussion as to whether these generative
rules are psychologically real.
• Early research in syntactic parsing attempted to
demonstrate that the complexity of a transformational rule
did, indeed, influence the listener’s ability to process a
sentence.
• The hypothesis was not supported.
Psycholinguistics
• Chomskyan thought has had a strong impact on
psycholinguistics in the area of language acquisition.
• Chomsky argues strongly for a nativist view.
• His main point relates to the ‘poverty of stimulus’ afforded
by child directed speech.
• The language to which the infant is exposed in its early
years could not possibly, he suggests, cover the whole
range of possible sentences.
• Furthermore, it is ‘degenerate’ in that it constitutes
performance data (complete with ungrammatical forms,
hesitations, false starts etc.).
• How then can the infant succeed in deriving competence
from it in a comparatively short time?
Psycholinguistics
• Chomsky concludes that we can only account for first language
acquisition by assuming that a child is born with an innate
knowledge of the principles of language and a predisposition to
employ them in analyzing the speech which it encounters.
• Current theory attempts to bridge the gap between the universal
principles with which we are born and the specific form of the
language which we finally acquire.
• We are said to be endowed with a Universal Grammar (UG) in the
form of an innate awareness of the nature of language and the
various forms that language adopts.
• UG is represented in terms of a set of principles common to all
languages and a set of parameters which are adjusted to reflect the
characteristics of the specific language to which the infant is
exposed.
Psycholinguistics
• CLUTTERING
• A disorder affecting fluency, in which the sufferer attempts
to speak too quickly, resulting in distorted articulation and
disrupted rhythm.
• Syllables may be truncated, words repeated, sounds
omitted or misarticulated.
• It is possible that planning at the phonetic level is
implicated: speech is uttered in staccato bursts, which
sometimes interfere with syntax.
• As the utterance proceeds, the speaker may well speed up
(festination) rather than slowing down.
• Cluttering sometimes occurs in conjunction with stuttering.
• One possible cause is brain damage.
Psycholinguistics
• COGNITION
• The use or handling of knowledge; hence, (a) the
faculty which permits us to think and reason and
(b) the process involved in thought and
reasoning.
• It is sometimes contrasted with metacognition,
which can be defined as ‘thinking about thinking’
and involves pre-planning a cognitive process,
exercising control over the process or taking steps
to ensure that its results are stored long term.
Psycholinguistics
• Metacognition involves some degree of
awareness, whereas cognitive processes may
not be available to report.
• An important issue is whether language is part
of general cognition or is a separate faculty.
• One argument supporting the latter (modular)
view is the fact that all normally developing
infants achieve a first language whatever their
cognitive capacities in other areas.
Psycholinguistics
• COGNITIVE PSYCHOLOGY
• The study of human mental processes and their contribution to
thinking, sensation and behaviour.
• The discipline is often traced back to Wundt, who founded a
psychology laboratory in Leipzig in 1879.
• Wundt’s method was to ask subjects to perform a mental process,
then report on the experience.
• This introspective approach produced inconsistent results.
• There was a strong reaction against it by psychologists who took an
anti-mentalist stand, arguing that the mind was unknowable.
• They insisted that the only scientific source of data for psychology
was human behaviour, which was observable in a way that mental
processes were not.
• From this grew the movement known as behaviourism.
Psycholinguistics
• Another influential movement in the early twentieth
century was led by the Gestalt group of psychologists,
who investigated how the mind shapes our perceptions
of the world.
• In particular, they examined how we perceive separate
elements (e.g. dots on a page) as falling into groups
and patterns.
• Reaction against behaviourism came from an
information processing approach developed in the
1950s which aims to chart the flow of information
through the mind as a particular cognitive task is
performed.
Psycholinguistics
• It underpins much current thinking in cognitive
psychology.
• From it has developed a view of much human
rational behaviour as based upon problemsolving; this has especially informed research into
the nature of expertise.
• A recent movement in cognitive psychology has
been connectionism, an attempt to model in
computer programs the neural networks which
form the basis of the operations of the brain.
Psycholinguistics
• COGNITIVISM
• Approaches to language acquisition which view the process
as closely linked to general cognition and to cognitive
development.
• Some accounts leave open the extent to which certain
aspects of language are innate; but all take the view that
acquisition is primarily driven by the way in which the
infant’s cognitive abilities are brought to bear upon the
input to which it is exposed.
• These cognitive abilities may reflect developing awareness
of objects, spatial relations, defining characteristics etc., or
they may take the form of perceptual biases which incline
the child to recognize patterns in linguistic material.
Psycholinguistics
• Among views on acquisition which can be characterized as
‘cognitive’ are:
• An infant cannot express concepts in language unless it has
previously developed them.
• Example: A child cannot use language to refer to objects that are
not visible unless it has grasped the idea of object permanence.
• For Piaget, language was the product of cognitive and perceptual
processes.
• His research with children led him to conclude that there were four
stages of cognitive development.
• They represent a gradual progression and not a sudden shift in
behaviour; and the age at which a particular child goes through
each varies considerably.
• However, they are closely linked to linguistic development.
Psycholinguistics
• Both language and cognition are part of a staged maturation program, in
which they operate in parallel, supporting each other.
• For Vygotsky, thought exists pre-verbally.
• There is initially a separation between thought and language: the infant’s
first words are devoid of thought.
• During three phases, the separate roles of thought and language become
established.
• Innate cognitive tendencies may predispose us:
• a. To find patterns in language data (as in data in general).
• A theory of syntactic bootstrapping postulates that infants reach
conclusions about words on the basis of their inflections and other
grammatical properties:
• thus the child learns that the difference between It’s sib and It’s a sib
serves to distinguish real-world entities that are mass from those that are
count.
Psycholinguistics
• b. To adopt certain strategies in response to language
data.
• Slobin (1973) concludes that infants apply a set of
universal strategies or operating principles in order to
deconstruct the input to which they are exposed.
• (Pay attention to the ends of words. Pay attention to
the order of words and morphemes.)
• More cognitively complex features are acquired later.
• c. To apply individual learning styles to language data.
Some infants appear to break the input into words,
while others acquire chunks of language in a holistic
manner.
Psycholinguistics
• The infant’s limited cognitive capacity renders
it more sensitive to the features of language
than it might be before or later.
• The ‘less is more’ argument holds that it may
be the very limitations of the infant’s early
cognitive state which enable it to identify
structure in language and to recognize that
language constitutes a set of inter-related
symbols.
Psycholinguistics
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COHORT THEORY
A model (Marlsen-Wilson, 1987) of the way in which words are retrieved from the
lexicon in listening.
A listener processes an utterance at a delay of around a fifth of a second behind
the speaker; this is often not enough to provide full evidence for a particular word.
Cohort Theory adopts the hypothesis that the listener retrieves a set of words (a
cohort) which match the evidence of the signal so far.
Thus, on hearing the phonetic string [k{p] they would retrieve CAP, CAPITAL,
CAPRICORN, CAPTURE, CAPTAIN, CAPTIVE, etc. as word candidates.
If the next sounds proved to be [t] and [I], the cohort would narrow to CAPTAIN,
CAPTIVE and CAPTIVATE.
Finally, the sound [n] would mark a uniqueness point, where only one word match,
CAPTAIN, was possible.
The uniqueness point of a word is not necessarily its last phoneme: for example,
the word PSYCHOLOGY becomes unique at the /l/.
Psycholinguistics
• A major objection to the early version of Cohort Theory was that it was
heavily dependent upon correct identification of word-initial phonemes.
• If a slip of the tongue led a speaker to produce ‘shigarette’ rather than
cigarette, the appropriate cohort would not be selected.
• In addition, account needs to be taken of phonetic accommodation,
which leads many words to diverge from their citation forms when they
occur in connected speech.
• The model was therefore revised to include a principle of closeness of fit
rather than exact match.
• An activation dimension was added: the cohort is now represented as a
set of lexical items whose strength is boosted or weakened by incoming
perceptual evidence until one of them achieves a match.
• Contextual evidence can play a role in narrowing down the cohort;
• but it is not taken into account until after about 150–200 milliseconds of
the word; this is referred to as bottom-up priority.
Psycholinguistics
• A weakness of the model remains the fact that it assumes
that a word is a discrete and easily identified unit.
• Many sequences that appear to constitute monosyllabic
words may prove instead to be the initial syllables of
polysyllabic ones, and vice versa.
• Using the ‘captain’ example, how is one to know if a match
has been achieved after the word CAP or if one has to
continue reducing the cohort?
• There may also be ambiguities of lexical segmentation
where word candidates cross boundaries (for example, the
word SISTER occurs within the sequence insist upon).
Psycholinguistics
• The ‘uniqueness’ concept has also been
challenged.
• A study of the lexicon has suggested that over a
third of words in normal speech are not unique
by their offsets, while there is evidence that
many monosyllabic words are not identified until
well after their offsets.
• Nevertheless, the notion of the cohort is
implicitly or explicitly adopted in many accounts
of auditory processing.