Williams Syndrome: Why do we study it

1
Williams Syndrome Why do we study it?

• Presentation for the EVOLUTION AND THE BRAIN
  focus group Collegium Budapest
• November 12, 2001
• Csaba Pléh

2
Working team

• Ilona Kovács, Ágnes Lukács, Mihály Racsmány and
  Csaba Pléh Support from OTKA (Hungarian National
  Research Found), McDonnel Foundation and NSFMain
  human resource Hungarian WS Association, Gábor
  Pogány and his group

3
What is Williams syndrome?

• Genetic damage, 1 in 20.000
• Multiple impairments joints, heart, fragile body
  structure, metabolism, voice.
• Brain development parietal, temporal
  undervelopment, cerebellar peculiarities.

4
Cognitive profile of WMS subjects

• moderate to severe mental retardation (IQ 50-80)
• intact face perception
• hypersociability
• relatively intact language skills
• counting problems
• impaired visual integration
• impaired spatial cognition

5
METHODS IN OUR STUDIES

• Verbal tasks
• Picture vocabulary
• Verbal working memory
• Suffix elicitation (morphology)
• 0bject names

• Visual tasks
• Contour integration
• Corsi blocks
• Rey matrices
• Spatial suffix learning
• Route learning

6
Stimuli in the picture naming task
Nouns Verbs
Compounds
Frequent
Rare
7
Stimuli in the morphology task
Regular cipo-cipok shoe-shoes
Irregular
bagoly-baglyok owl-owls
8
Picture naming, word class and frequency
9
Main issues in our linguistic tasks

• Question 1 How frequency dependent is the
  lexicon in WMS subjects ?
• Question 2 Is their a general tendency for
  overgeneralizations in an agglutinative language?
  
• Question 3 What is the relationship between
  overgeneralizations and frequency in WS?
• Question 4 The role of working memory in
  vocabulary and overgeneralizations and

10
Stimuli in the picture naming task
Nouns Verbs
Compounds
Frequent
Rare
11
Stimuli in the morphology task
Regular cipo-cipok shoe-shoes
Irregular
bagoly-baglyok owl-owls
12
Picture naming, word class and frequency
13
Regressions predictors for vocabulary (WS group)
 
   
14
Stem classes and frequency in Hungarian
15
Error patterns in regulars and irregulars
16
Overgeneralizations in v stems
17
Morphological errors and memory span
Effects of verbal STM span Regulars
F(2,13)5.72, plt.05 Irregulars (2,13)6.61, plt.05
18
Conclusions (language)

• Based on a picture naming task, there is
  frequency sensitivity in the WS vocabulary.
• Vocabulary size (especially with rare words) and
  morphological performance is closely related to
  the capacity of verbal short-term memory, even
  after controlling age effects higher working
  memory span predicts larger vocabulary size and
  less errors with irregular inflection.
• Frequency sensitivity might be mediated by
  working memory children with higher working
  memory span learn less frequent words more
  easily.
• Grammatical development of WS children might also
  be supported by their relatively intact
  phonological short-term memory.

19
Verbal and spatial working memory capacity in
Williams syndrome
20
Rey matrices
21
Where further?

• More specific studies on grammar
• The detailed analysis of problems in spatial
  language and their relations to spatial problems
• Where do memory differences come from?