Download Causation in Child Language Disorders DES 320

Causation in Child Language
Disorders
DES 320
Syndrome
“the presence of multiple anolalies in
the same individual with all of thoses
anomalies having a signle cause”
(Sprintzen, 1997)
Examples: facial features, structural
abnormalities, hearing/speech
problems
Etiologies of language disorders
Impoverished language input
Hearing impairments
Deprivation
Conditions where neural development is affected
Syndromes
Congenital syndromes
– Chromosomal abnormalities
– Genetic syndromes
– Teratorgenic: in utero diseases and toxins
Diseases and toxins after birth
Acquired aphasia in childhood
Unknown causes (presumably neural development
is afffected)
Impoverished language
input…Hearing Impairment
Middle Ear: transmission of sound from
the auditory canal into middle ear
(conductive hearing loss)
Inner Ear: transmission of sound into
neuronal firing
(sensorineural hearing loss)
Spoken language development in
hearing losses depends on:
Degree of hearing loss (profound, severe,
moderate, mild)
Unilateral or bilateral
Age of onset
Audiometric slope of the loss (for ex. High
frequency vs. low frequency affects perception of
different phonemes)
Age of identification
Amplification (functional or not)
Amount and type of habilitation (ASL, auditoryoral, total communication)
Educational environment
Family support or lack thereof…
Otitis Media: impact on language
development
Does fluctuating conductive hearing loss
due to otitis media effusion (OME) cause
language disorders?
Possible phonological disorders…1/3 of kids
receiving Speech or language intervention have
a hx of OME
Pontentially problems in other areas of
langauge…evidence is contradictory…
OME usually associated with phonological
impairment
OME may be a risk factor that must occur with
something else in order to cause a language disorder
Impoverished Language
Input…Language Deprivation
Neglect
Hard to show causality because these
are often children with multiple
problems
Physical abuse, emotional abuse, sexual
abuse, parental alcohol & drug abuse
Disabilities
Language gains depend on age of
child
Nervous System
The rest of the causes we will discuss
affect development of the nervous
system…often times in ways in which we
don’t understand
More plasticity & less cerebral localization
in children
Effects on language seen in focal damage in
adults not seen in children
Damage limited to left hemisphere Broca’s or
Wernicke’s areas doesn’t explain language
problems in developmental disorders
Syndromes involving genes…
Chromosomal abnormalities
Addition or deletion of whole chromosomes
Addition or deletion of parts of chromosomes
Restructuring or rearranged chromosomes
Genetic syndromes
Run in families
Affected gene(s) may or may not be discovered
yet (ex. Chromosome 19 in my family)
Chromosomal abnormalities
Run in family or randomn genetic mutation
Disorders: Hearing loss
Autosomal chromosomes (1-22)
Disorders: Down syndrome, Cri du chat, Williams
Syndrome
Sex chromosomes: #46
Female – XX & Male – XY: a parent can be normal, a
carrier or affected…the combination of sex chromosomes
that the parents pass onto a child impact whether the
child is normal, a carrier or affected….
Disorders: Fragile X, Kleinfelter syndrome, Turner
Syndrome
In utero origins of syndromes
Maternal diseases
Rubella, Cytomegal Virus (CMV),
Herpes simplex, Syphilis, Toxoplasmosis
Toxins
X-radiation, smoking, cocaine & other
illegal drugs
Legal drugs (prescriptions, etc.)
Fetal alcohol syndrome
Mental retardation, small size, cleft palate,
abnormalities of face and ear
During or after birth origins of
syndromes
Complications during birth…premature
birth
Intraventricular hemorrhage
Respiratory disorders: anoxia – oxygen
deprivation to the brain
Infections & toxins
measles, mumps
Meningitis
Lead (in paint in older houses, older toys)
Acquired Aphasia in childhood
Head injury
Brain tumors
Rare instances of stroke
Recovery
The site of damage is less influential
than in adults
The extent of damage is more important
Case
When I met Emma, she was 5 years old and living
in a foster home. She (along with her older
brother) had lived with biological mom for the first
four yrs. Of her life. In Emma’s past was evidence
of a head injury due to physical violence, maternal
alcohol abuse and being locked in her room for
extended periods of time. Emma’s main difficulty in
the area of language was lexical and phonological
processes. She was substituting and deleting
sounds. She also had small vocabulary and word
finding difficulties. When she learned new words,
she had difficulty retaining them over time. What
was the cause or etiology of Emma’s phonological
and lexical difficulties? Why is causality a slippery
slope in language disorders?
Disorders with unknown etiologies
Presumably disorders of central
nervous system development
Landau-kleffner syndrome
Autism
SLI
Dyslexia
Thought Question…
What do we know about causation in
language disorders? Think about
today’s lecture notes and also our
previous discussion about the
relationship between cognition and
language development…
What do we not know?
Thought Question…
If language disorders are impacted by
genetic and/or neurological factors,
how much of an impact do you think
environmental influences have on the
prognosis for remediation? What can
we do as SLPs to prevent language
disorders or lessen their severity?