LIGN171: Child Language Acquisition http://ling.ucsd.edu/courses/lign171 http://ling.ucsd.edu/courses/lign171 LIGN171: Child Language Acquisition Developmental Developmental Disorders affecting Disorders affecting language language Williams Syndrome Williams Syndrome
Williams Syndrome (WS) Williams Syndrome (WS) � Discovered in 1964 � Infantile hypercalcemia (excess calcium) � 1/7500 children � Genetic Disorder � Deletion/mutation of genes on chromosome 7q11.23 � Many protein deficiencies � Elastin is a protein found thoughout the body
Medical Phenotype Medical Phenotype Characteristic facial appearance � Abnormal growth pattern � Low birth weight � Early puberty � Shorter than normal growth spurt in � puberty Hypercalcemia (excess calcium) � Hypotonia; hyperreflexia � Cerebellar problems � Opthomalogic problems � Hypersensitivity to sound � Dental problems � Connective tissue abnormalities � Skin, joints � Cardiovascular � Gastrointestinal problems � Urinary tract abnormalities � Musculoskeletal problems �
Cognitive Phenotype Cognitive Phenotype � Relatively good auditory Relatively good auditory � rote memory rote memory � Relatively good language Relatively good language � � But But delayed acquisition! delayed acquisition! � � Very poor Very poor visuo visuo- -spatial spatial � abilities abilities � Highly social/overfriendly Highly social/overfriendly � � “ “delightful delightful” ” � � Attention deficit disorder Attention deficit disorder � � Anxiety Anxiety � � Full Full- -scale IQ around 50 scale IQ around 50 � � IQ excluding spatial tests IQ excluding spatial tests � (K- -BIT) ranges from 40 BIT) ranges from 40- - (K 102; mean 66 102; mean 66
K- -BIT (non BIT (non- -spatial) IQ spatial) IQ K
Visuo- -spatial abilities spatial abilities Visuo � Very poor Very poor � � Focus on details Focus on details � � Poor on block design Poor on block design � � Not a deficit of visual Not a deficit of visual � perception perception � Perception not worse than Perception not worse than � age and IQ- -matched matched age and IQ controls controls � Face perception seems to Face perception seems to � be relatively strong be relatively strong
Brain Findings Brain Findings � Overall reduction in volume (but small size in Overall reduction in volume (but small size in � general, not just brain) general, not just brain) � Controlling for overall volume Controlling for overall volume � � Reduced volume Reduced volume � � Parietal cortex Parietal cortex � � Corpus Corpus callosum callosum � � Brainstem Brainstem � � Increased volume Increased volume � � Auditory cortex (temporal lobe) Auditory cortex (temporal lobe) � � Cerebellum Cerebellum � � Increased cortical Increased cortical gyrification gyrification/complexity /complexity � � Abnormal Abnormal hippocampal hippocampal shape shape � � Atypical neuron size and packing Atypical neuron size and packing �
2 Theories (1) 2 Theories (1) � Language Modularity Language Modularity � � Preserved language in Williams Syndrome suggests Preserved language in Williams Syndrome suggests � that language is independent of cognition that language is independent of cognition � What is a module? What is a module? � � Specialized, encapsulated processor Specialized, encapsulated processor � � Granularity problem Granularity problem � � What is modular about language? What is modular about language? � � All of it? All of it? � � Just Syntax? Morphology? Phonology? Just Syntax? Morphology? Phonology? � � Particular Particular morphosyntactic morphosyntactic rules? rules? �
2 Theories (2) 2 Theories (2) � Neuro Neuro- -constructivist constructivist � � Williams syndrome is a developmental disorder Williams syndrome is a developmental disorder � � Language in Williams syndrome reflects altered Language in Williams syndrome reflects altered � constraints on cognitive and linguistic development constraints on cognitive and linguistic development � Early language studies important, before Early language studies important, before � compensation can take place compensation can take place � Two hypotheses Two hypotheses � � Over Over- -reliance on spared phonology reliance on spared phonology � � (phonological short term memory) (phonological short term memory) � � Lexical Lexical- -semantic processing is impaired semantic processing is impaired � � “ “Conservative hypothesis Conservative hypothesis” ” � � Language is delayed but normal Language is delayed but normal �
A difficulty… … A difficulty � What is benchmark for What is benchmark for ‘ ‘normal normal’ ’ language? language? � � Chronological Chronological- -age matched typical controls? age matched typical controls? � � But large IQ differences But large IQ differences � � Mental Mental- -age matched typical controls? age matched typical controls? � � But large chronological age differences But large chronological age differences � � Chronological and mental Chronological and mental- -age matched age matched � atypical controls? atypical controls? � Other disorders may be different in many ways Other disorders may be different in many ways �
Language Profile in Language Profile in Williams Syndrome Williams Syndrome Is it really spared? Is it really spared?
Pragmatics Pragmatics � Use of language in a social context Use of language in a social context � � Early studies suggest spared pragmatics Early studies suggest spared pragmatics � � BUT BUT � � Old fashioned/formal style Old fashioned/formal style � � Failure to respond adequately to questions Failure to respond adequately to questions � � Focus on irrelevant topics in conversation Focus on irrelevant topics in conversation � � WS make fewer inferences about mental states than WS make fewer inferences about mental states than � controls controls � “ “cocktail party speech cocktail party speech” ” � � Fluent speech; Fluent speech; overfamiliar overfamiliar manner, etc. manner, etc. � � Impaired at figurative/non Impaired at figurative/non- -literal language literal language � � Lies, jokes Lies, jokes �
Syntax Syntax � Receptive Receptive � � Normal comprehension of Normal comprehension of � � Reflexives ( Reflexives (‘ ‘himself himself’ ’) ) � � Passives Passives � � Complex embedded clauses Complex embedded clauses � � Receptive syntax worse than receptive vocabulary Receptive syntax worse than receptive vocabulary � � Expressive Expressive � � Parent interview indicates comparable complexity of sentences Parent interview indicates comparable complexity of sentences � in WS and typical controls, both better than Down syndrome in WS and typical controls, both better than Down syndrome � Spontaneous speech samples suggests normal complexity and Spontaneous speech samples suggests normal complexity and � mean length of utterance (MLU) mean length of utterance (MLU) � Sentence repetition impaired in Italian Sentence repetition impaired in Italian � � Impaired elicited production of relative clauses Impaired elicited production of relative clauses � � Apparently no compensation by rote learning Apparently no compensation by rote learning �
Morphology Morphology � Regular vs irregular plural or past tense Regular vs irregular plural or past tense � � English, German, Hungarian English, German, Hungarian � � Relative to matched control subjects Relative to matched control subjects � � Regulars seem to be largely spared Regulars seem to be largely spared � � Possibly impaired in some cases Possibly impaired in some cases � � Irregulars seem to be impaired Irregulars seem to be impaired � � Novels seem to be spared in some cases, impaired in Novels seem to be spared in some cases, impaired in � others others
Phonology Phonology � Phonology in WS Phonology in WS � � Speech perception biased towards prosody Speech perception biased towards prosody � � Trouble (delays) with syllables/phonemes Trouble (delays) with syllables/phonemes � � Speech production appears normal Speech production appears normal � � Normal relationship with motor development Normal relationship with motor development � � Phonological short term memory Phonological short term memory � � “ “peak ability peak ability” ”? ? � � Better at digit span and word span than Down Better at digit span and word span than Down � syndrome (weakness) syndrome (weakness) � Not better than typical controls Not better than typical controls �
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