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• Williams Syndrome (WS):– (more or less) general cognitive retardation except in language– Results from the deletion of the long arm of chromosome 7.
• Specific Language Impairment (SLI):– Language problems without any obvious cause.– fifty to seventy percent of children with SLI have at least one other
family member with the disorder
If the brain is a general purpose problem solver, one’sgeneral intelligence should be predictive of abilities such aslanguage.
For people affected by WS or SLI that’s simply not true.
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A genetic marker for WMS isthe deletion of one copy ofa small set of genes onchromosome 7, band 7qll23,shown in the ideogram. Thisregion is expanded to theright to illustrate genes thatare missing one copy inWMS, including the gene forelastin. The regions involvingthe common breakpoints inWMS are also illustrated (seeKorenberg et al., this volume).Thus, WMS is characterizedgenetically by deletion of onecopy of a small set of geneson chromosome 7, includingthe gene for elastin(illustration based onKorenberg et al., 1998).
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Total volume of the brain is reduced in WS but frontal lobe,neocerebellum, temporal limbic areas and superior temporal areas arepreserved or even enlarged.
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Neocerebellum– Involved in movement.– Among the brain's newest parts, appearing in human ancestors
about the same time as the enlargement of the frontal cortex, whichcontrols much of rational thought and reasoning.
– The neocerebellum is significantly smaller in people with autism,who are generally antisocial and poor at language, the reverse ofpeople with Williams.
Limbic system– memory, emotions
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Neurocognitive predictions
• Impairment on right hemisphere functions.• Relative sparing of left hemisphere function.
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Williams Syndrome (WS) medical features
• enhanced musical ability• relatively spared language• overly friendly personality
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Williams Syndrome (WS) medical features
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Williams Syndrome (WS) medical features
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Williams Syndrome (WS) medical features
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• Spatial cognition tasks
Persons with WS are bad at:
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Model:
Williams
Age 11;1
Williams
Age 9;1
Control
Age 6;1
From: http://www.ling.udel.edu/colin/courses/ling101_f98/lecture1.html
12http://www.udel.edu/PR/UDaily/2004/WSDrawingslg.jpg
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Persons with WS are bad at:
• Spatial cognition tasks– But they know that their models are not correct.
• Contrast between visuo-spatial and language abilities:
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Persons with WS are bad at:
• Spatial cognition tasks
• Distinct modes of failure in WS and Down:
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Persons with WS are bad at:
• Piagetian conservation tasks– Ability to recognize that number, mass or volume
does not alter when physical appearance alters.– E.g. =
• Math and number concepts• Folkbiology (Johnson & Carey, 1998)
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Persons with WS are good at:
• Music.– Individuals with WS generally have a higher rate of
musicality.– WS persons tend to have an “affinity” for music --
this, however, does not necessarily entail musicaltalent.
– The percentage of individuals with Williamssyndrome who have perfect pitch is higher than thepercentage among individuals in the generalpopulation.
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Persons with WS are good at:
• Auditory short term memory.– Recall: This is precisely what’s impaired in dyslexia
and SLI
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Persons with WS are good at:• Face processing.
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Persons with WS are good at:
• Theory of mind
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Persons with WS are good at:
• Language– But there is a debate about whether language is
really spared.
For excellent resources on this debate, see Andrea Zukowski’s UMD website:http://www.ling.umd.edu/zukowski/
http://www.ling.umd.edu/zukowski/zukowski.pdf
– For example, it’s been shown that WS kids performbadly on emdedded relative clauses.
((KarmiloffKarmiloff-Smith et al, 1997; -Smith et al, 1997; Volterra Volterra et al.,1996; et al.,1996; Mervis Mervis et al., 1999)et al., 1999)
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What does the test look like?What does the test look like?
““The circle the star is in is redThe circle the star is in is red””
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• Hardly surprising if a person with general mental retardation does not do so well on thistask.• Challenge: to devise tasks that tap ontolanguage without being taxing for other cognitiveresources.
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Example(from Zukowski’s work)
Method: Elicited production techniqueMethod: Elicited production technique(Hamburger and Crain, 1982)(Hamburger and Crain, 1982)
Children are asked to tell a parent which ofChildren are asked to tell a parent which oftwo similar characters a change happened to.two similar characters a change happened to.
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Which cow is Max looking at?
27““The cow who um the boyThe cow who um the boy’’s pointing to.s pointing to.””
(12-year-old Williams Syndrome male, IQ = 56)
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(12-year-old Williams Syndrome male, IQ = 56)
ObjectObjectGapGap
RelativeRelative
““The cow The cow who um the boywho um the boy’’s pointing tos pointing to..””
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Which boy turned blue and which boyWhich boy turned blue and which boyturned purple?turned purple?
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““The boy thatThe boy that’’s pointing to his arms pointing to his armturned purple,turned purple,
and the boy that turned blueand the boy that turned blueis pointing to his fingeris pointing to his finger””
(16-year-old Williams Syndrome male, IQ = 40)(16-year-old Williams Syndrome male, IQ = 40)
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““The boyThe boy that that’’s pointing to his arms pointing to his armturned purple,turned purple,
and the boyand the boy that turned blue that turned blueis pointing to his fingeris pointing to his finger””
(16-year-old Williams Syndrome male, IQ = 40)(16-year-old Williams Syndrome male, IQ = 40)
SubjectSubjectGapGap
RelativesRelatives
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““The boyThe boy thatthat’’s pointing to his arms pointing to his armturned purple,turned purple,
and the boyand the boy that turned bluethat turned blueis pointing to his fingeris pointing to his finger””
(16-year-old Williams Syndrome male, IQ = 40)(16-year-old Williams Syndrome male, IQ = 40)
Center-Center-embeddedembeddedstructuresstructures
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What was each WS individualWhat was each WS individualcapable of producing?capable of producing?
ChildSG
RelativeOGRelative
CERelative
RBRelative
1 2 3 4 5 6 7 8 9 10
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Control ChildrenControl Children
ChildSG
RelativeOGRelative
CERelative
RBRelative
1 2 3 4 5 6 7 8 9 10
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Every WS child except oneEvery WS child except onewas capable of producing examples ofwas capable of producing examples of
each of the components ofeach of the components ofembedded relative clausesembedded relative clauses
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• WS kids produce complex syntactic structuresas long as the task demands are otherwiselow.
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Individuals with Down’s and Williams Syndromeshave similar IQs
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WS and irregular vs. regular morphology
• Overregularization of irregulars in WS (Clahsen etAlmazan; Clahsen et al 2003.
– “rules” are intact; lexical memory is impaired. Taken asevidence for dual mechanism theories morphology.
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Zukowski (2001): WS regular vs. irregularmorphology
(1) What’s this?
(2) And here are a bunch of…?
(3) What would you call someone whoeats…?
A FOOT!
A RAT!
FEET!
RATS!
FEET-EATER!
RAT-EATER!
*RATS-EATER!
• Gordon (1985): kids as young as 3 years never producerats-eater.
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Zukowski (2001): WS regular vs. irregularmorphology
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Zukowski (2001): WS regular vs. irregularmorphology
• What about WS kids? Producing regulars is very easyfor them while producing irregulars is hard. Would WSkids produce rats-eater?
– No, never.
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