Williams Syndrome
and the Issue of
Neurogenetic Developmental Disorders
May
1-5, 2002, Budapest, Hungary
Organized by
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the Collegium Budapest and
Center for Cognitive Science, Budapest
University of Technology and Economics |
Supported by
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the National Science Foundation
Children's Research Initiative USA |
Conference site:
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Collegium Budapest
Institute for Advanced Study
H-1014 Budapest, Szentháromság utca 2.
Tel (36-1) 224-8300
Fax (36-1) 224-8310
http://www.colbud.hu |
Accommodation:
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Guesthouse of the Academy of Sciences
H-1014 Budapest, Országház utca 21.
Tel (36-1) 457-8090 |
Table
of contents
List
of Participants. 4
Speakers. 4
Focus
Group Of Collegium Budapest. 4
Research
Associates. 4
Overview
of the program.. 5
Detailed
scientific program.. 6
Abstracts. 8
Language
profiles in WS. 8
Virginia
Volterra: Early linguistic abilities in Italian children with WS. 8
Ágnes
Lukács: Frequency effects in the WS mental lexicon. 8
Michael
Thomas: Computational modeling of language acquisition in Williams syndrome:The
case of past tense formation.9
Farrell
Ackerman: Pausing to consider: A lexicalist appraisal of dual mechanism
models and Williams Syndrome research in morphology. 9
Sociality:
WS and autism. 11
Miklós
Gy?ri: Fractionating 'theory of mind': evidence from autism. An overview. 11
Zsuzsa
Káldy: What mechanisms affect the unusual social profile of Williams
Syndrome individuals?. 11
Determinants
of development in WS (Public Session)12
Ursula
Bellugi, Edward S. Klima: Linking Cognitive Neuroscience and Molecular
Genetics: New Perspectives from Williams Syndrome. 12
Annette
Karmiloff-Smith: Genotype Phenotype Relations: Why a Cognitive Developmental
Perspective is Crucial13
Visual
organization in WS. 14
Janette
Atkinson: Visuo-Spatial Cognition, Attention And Frontal Function In WS
Children. 14
Ilona
Kovács: Low-level Perceptual Deficit in Williams Syndrome. 15
Katarina
Jariabková: Visuo-constructive abilities in individuals with Williams
syndrome and Down syndrome as assessed by Rey-Osterrieth Complex Figure. 16
WS
and working memory. 17
Chris
Jarrold: Causes and consequences of poor visuo-spatial short-term memory
in Williams syndrome. 17
Mihály
Racsmány: Dissociated components of working memory and their effects
on long-term acquisition in WS. 18
Methods
Measuring vision Memory measures and neuropsychology. 19
Gábor
Pogány: Foster the development of self–help consciousness in families
of WS children by interacting with researchers19
Chris
Jarrold: Methods of assessing short-term and working memory. 20
List
of Participants
Speakers
U.
Bellugi, Salk Institute, Laboratory for Cognitive Neuroscience, bellugi@salk.edu
G.
Csibra, Centre for Brain and Cognitive Development School of
Psychology, Birkbeck Collegeg.csibra@bbk.ac.uk
E.
Klima Salk Institute Laboratory for Cognitive Neuroscience,
I.
Kovács, Rutgers Department of Psychology, ikovacs@cyclops.rutgers.edu
A.
Lukács, MTA Budapest Linguistics Institute, alukacs@axelero.hu
Cs.
Pléh, BME and Collegium Budapest, pleh@itm.bme.hu
G
Pogány, Semmelweis Med. University, Budapest and Hungarian
Williams Syndrome, Association, pogany@williams.ngo.hu
M.
Racsmány, SZTE Szeged, racsmany@edpsy.u-szeged.hu
M.
Thomas, London Institute of Child Health, mthomas@ich.ucl.ac.uk
V.
Volterra, Institute for Cognitive Science and Technology, Rome volterra@www.ip.rm.cnr.it
Focus
Group Of Collegium Budapest
Z. Breznitz
V. Csányi
D. Bickerton
E. Szathmáry
B. Nánay
Research
Associates
E. Barótfi
N.
Hahn
H.
Jolsvai
I. Király
A. Ragó
Overview
of the program
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May 1.
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ARRIVALS
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17:20
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We will take you to the boat landing from the
Guesthouse
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18:00-20:00
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River-boat excursion in the afternoon (Boat
is named Hófehérke, Snow-white)
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20:00-
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Dinner at Dunaparti
Vedégl?, Halász utca 1.
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May 2.
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MODELS AND DATA
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9:00-13:00
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Morning session:
Language profiles in WS (Lukács,
Ackerman, Volterra, Thomas) |
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14:00-16:00
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Afternoon session:
Sociality: WS and autism (Gy?ri,
Káldy) |
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17:00-19:00
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Public session (evening):
Determinants of development in WS (Bellugi, Karmiloff-Smith) |
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20:00-
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Dinner in small groups
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May 3.
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MODELS AND DATA
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9:00-13:00
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Morning session:
WS and working memory (Jarrold, Racsmány) |
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14:00-17:00
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Afternoon session:
Visual organization in WS (Atkinson, Kovács, Jariabková) |
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17:00-
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Occasional sight seeing
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19:00-
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Opera for those who signed up
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May 4.
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INTERACTIONS
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9:00-11:00
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Interactions between parents and scientists (Pogány)
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13:00-17:30
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Afternoon session:
Methods Vision Memory and neuropsychology
(Pogány, Jarrold)
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19:00-
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Evening party at Csaba Pléh
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May 5.
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Free program
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Detailed
scientific program
|
|
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MODELS AND DATA
|
|
|
9:00-13:00
|
Morning session:
Language profiles in WS
(Volterra, Lukács, Thomas, Ackerman) |
|
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9:00-9:45
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Virginia Volterra Early linguistic abilities
in Italian children with WS
|
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9:45-10:30
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Ágnes Lukács: Frequency effects
in the WS mental lexicon
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|
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10:30-11:00
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Coffee break
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11:00-11:45
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Michael Thomas: Computational modeling of language
acquisition in Williams syndrome: The case of past tense formation
|
|
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11:45-12.30
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Farrell Ackerman: Rules and WS general discussion
on language
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12:30-14.00
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Lunch
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14:00-16:00
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Afternoon session:
Sociality: WS and autism (Gy?ri,
Káldy) |
|
|
14:00-14:45
|
Miklós Gy?ri:Fractionating
'theory of mind': evidence from autism
|
|
|
14:45-15:30
|
Zsuzsa Káldy: What mechanisms affect
the unusual social profile of Williams Syndrome individuals?
|
|
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15:30-16.00
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Discussion on sociality and WS
|
|
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16.00-16.30
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Coffee break
|
|
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17:00-19:00
|
Public session:
Determinants of development in WS
(Beluggi, Karmiloff-Smith) |
|
|
17:00-18:00
|
Ursula. Bellugi & Edward. Klima: Linking
Cognitive Neuroscience and Molecular Genetics: New Perspectives from Williams
Syndrome
|
|
|
18:00-19:00
|
Annette Karmiloff-Smith: Genotype Phenotype
Relations: Why a Cognitive Developmental Perspective is Crucial
|
|
|
20:00-
|
Dinner in small groups
|
|
|
|
MODELS AND DATA
|
|
|
9:00-13:00
|
Morning session:
Visual organization in WS
(Atkinson, Kovács, Jariabková) |
|
|
9:00-9:45
|
Janette Atkinson: Visuo-Spatial Cognition,
Attention And Frontal Function In WS Children
|
|
|
9:45-10:30
|
Ilona Kovács: Low-level Perceptual Deficit
in Williams Syndrome
|
|
|
10:30-11:00
|
Coffee break
|
|
|
11:00-11:45
|
Katarina Jariabková: Visuo-constructive
abilities in individuals with Williams syndrome and Down syndrome as assessed
by
Rey-Osterrieth Complex Figure |
|
|
11:45-12:45
|
General discussion on vision
|
|
|
12:45-14:00
|
Lunch
|
|
|
14:00-16:00
|
Afternoon session:
WS and working memory (Jarrold, Racsmány) |
|
|
14:00-14:45
|
Chris Jarrold: Causes and consequences of poor
visuo-spatial short-term memory in Williams syndrome
|
|
|
14:45-15:30
|
Mihály Racsmány: Dissociated
components of working memory and their effects on long-term acquisition
in WS
|
|
|
15:30-16:00
|
General discussion on memory
|
|
|
16:00-
|
Occasional sight seeing
|
|
|
19:00-
|
Opera for those who signed up
|
|
May 4.
|
|
INTERACTIONS
|
|
|
9:00-11:00
|
Interactions between parents and scientists
(Pogány)
|
|
|
13:00-17:30
|
Afternoon session:
Methods: Life, vision Memory and neuropsychology
(Pogány, Jarrold) |
|
|
|
Gábor Pogány: Foster the development
of self–help consciousness in families of WS children by interacting with
researchers (Video about Hungarian WS children)
|
|
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14:00-15:00
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Vision methods (discussion organized by Ilona Kovács)
|
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15:00-16:00
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Chris Jarrold Methods of assessing short-term
and working memory
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16:00-17:00
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Language methods (discussion organized by Ágnes
Lukács)
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Abstracts
Language
profiles in WS
Virginia Volterra:
Early linguistic abilities in Italian children with WS
Rome Institute of Psychology
(with M.Cristina Caselli, Olga Capirci, Stefano
Vicari, Francesca Tonucci)
Previous studies of linguistic abilities in Italian-speaking
children with WS and DS are briefly reviewed. New data on linguistic performance
of 6 Italian children with WS between 3 and 6 years are presented and compared
with data on linguistic performance of 6 children with DS matched for chronological,
mental age and vocabulary development and of 6 normally developing younger
children, matched for mental age and vocabulary. The language measures
included also a parent report of early phrase structure, a naming test
and a Sentence Repetition Test. Analyses revealed that the three groups
of children were at the same vocabulary level, but showed different patterns
in sentence production and repetition. Children with WS produced more complete
sentences, similar to normally developing children at the same mental age,
whereas children with DS produced more telegraphic and incomplete sentences.
The difference between children with DS and WS was more marked on the repetition
task, suggesting that phonological short-term memory may play a greater
role when sentence production is measured through repetition.
Particularly interesting is the comparison between
the tree groups in the errors produced in the repetition task These results
from younger children confirm and extend previous findings with older children
and adolescents with WS. They further suggest that the apparently spared
linguistic abilities of children with WS could emerge as an artifact of
comparisons made with children with DS, whose sentence production competence
is more compromised relative to other verbal and non-verbal abilities.
More recent data collected with more children will
also be presented and discussed.
Ágnes Lukács:
Frequency effects in the WS mental lexicon
MTA Linguistics Institute, Budapest
One of the most often cited characteristics of Williams
syndrome is the tendency of WS people to use infrequent or strange words.
This everyday observation has been tested in several experimental situations,
the findings of which are still contradictory. We present results from
a semantic fluency task, in which subjects had to produce as many category
examples as they can in one minute. 11 WS subjects and controls matched
in vocabulary level were tested in 8 categories: food, drinks, animals,
furniture, clothes, musical instruments, things to read, jobs. Our
results are in concert with previous findings by Jarrold et al., (2000):
WS subjects and controls did not systematically differ in the number of
category items produced in 1 minute (with WS subjects producing more items
only in the drinks category). Using category norms as frequency
measures, we did not find any difference between the two groups in the
average frequency of the items, and no differences were found in the number
of non-category items they listed as category members either. WS subjects,
though, produced more items with zero frequency in three categories: animals,
food
and
drinks,
which are probably the most highly structured and richest categories for
children. The lack of systematic differences in frequency between the two
groups is supported by our previous results from a picture-naming vocabulary
task, in which the WS group, just as controls, performed better with frequent
words than with infrequent ones. Although further research is necessary,
taken together, our results indicate that frequency is an organizing principle
of the WS mental lexicon that operates in the same way as in normals, and
peculiarities of WS word usage has to be explained by some other factor.
Michael
Thomas:
Computational modeling of language acquisition in Williams syndrome:
The case of past tense formation.
Institute of
Child Health, London
Connectionist
models provide a tool to explore processes of cognitive development, and
by extension, atypical development found in developmental disorders. Language
development in Williams syndrome (WS) has been characterized as demonstrating
selective deficits, with grammatical processes developing normally but
processes relating to word-specific knowledge showing deficits. Selective
deficits for irregular verbs in English past tense acquisition have been
cited as evidence supporting this claim. WS has then been used to make
theoretical claims about the structure of the normal language system. In
this talk I will describe the most recent empirical evidence on past tense
acquisition in WS. I will then introduce a connectionist model of past
tense acquisition, and demonstrate how atypical computational constraints
in the start state of the model may allow the model to capture the WS profile
of past tense acquisition. The model will be used to evaluate the viability
of five hypotheses of how language development in WS may be atypical, identified
from an extensive review of the literature. The model suggests several
constraints may be atypical in the WS language system.
Farrell
Ackerman: Pausing to consider:
A lexicalist appraisal of dual mechanism models and Williams Syndrome
research in morphology
Dept.
of Linguistics UC San Diego
Over
the past decade proponents of the so-called Dual Mechanism model (Pinker
1999, among others) as well as their opponents (most relevantly, Thomas
et. al. 2001) have investigated a small number of inflectional phenomena,
and generated a large debate. For example, in the domain of German and
English plural number marking the former have claimed that the contrast
between regular plural inflection versus irregular plural inflection internal
to compounding, * rats
eater mice eater,
respectively, reflects the rule-based default status of the regular plural
and the stored lexical status of the irregular plural. Roughly, the claim
is that rule generated words are not stored in the lexicon and therefore
cannot serve as input to lexical operations such as compounding, while
the lexically stored status of irregulars makes them possible candidates
for lexical operations such as compounding. Methodologically the logic
of the research among proponents of the dual mechanism approach is clear.
Experimental results in several domains of inflectional morphology (past
tense, plural marking, regular inflection-inside compounding, comparatives)
among unimpaired populations are provided with a theoretical explanation
in terms of an opposition between rule-based explanation for regular formations
versus an associative-based explanation for irregular formations. The same
phenomena are then investigated within special populations where observed
dissociations are adduced as evidence for the theoretical division of labor
between rules and analogy. This basic strategy has been applied by Clahsen
& Almazan 2001 to compounding and Clahsen and Almazan to appear to
comparatives in English William Syndrome populations. I will examine issues
concerning (ir)regular plural marking, (ir)regular plural marking internal
to compounds, and comparative formation since they are phenomena utilized
in experiments with William Syndrome populations. Specifically, I will
show that experimental and diary data from Finnish first language acquisition
demonstrate that, contra expectations of the dual mechanism model, there
is regular case inflection internal to compounding, as in Hungarian. Among
other things, this suggests that complete and detailed analyses of the
relevant phenomena in a wide scatter of languages are crucial before one
can draw reliable inferences from their behavior in either unimpaired or
special populations. I then look at some derivational operations, particularly
with respect to predicate formation operations in Hungarian (see Clahsen
et. al. ms. for an intriguing comparison of inflection and derivation among
competing morphological models) and argue that theories of morphology in
both inflection and derivation need to provide principled ways of capturing
gradient degrees of productivity and regularity. Promising lines of inquiry
will be drawn from proposals by Jackendoff 1975, Bochner 1993, and Riehemann
1999, 2001. In all instances I try to provide research questions for further
study of morphology within the Hungarian Williams Syndrome population (Pl J h
& Luk <cs
to appear). In this connection, I will suggest that the debate between
advocates of a dual mechanism approach and advocates of a single mechanism
has been artificially narrow, neglecting, for the most part, instructive
research from other traditions in which considerable effort has gone into
elaborating the structure of the lexicon and in which morphology is regarded
to be a distinct domain, irreducible to either syntactic or phonological
principles. I take a perspective on the relevant issues less familiar to
psycholinguists and neurolinguists: a unification-based lexicalist perspective
on grammar (LEXICAL
FUNCTIONAL GRAMMAR (Bresnan
2001, Dalrymple 2001, HEAD
DRIVEN PHRASE STRUCTURE GRAMMAR (Sag
and Wasow 1999), and CONSTRUCTION
GRAMMAR (Fillmore
and Kay ms. Ginzburg and Sag 2001) and a inferential-realization perspective
on morphology (Robbins 1959, Matthews 1972, Zwicky 1989, Anderson 1992,
Aronoff 1994, Spencer 2001, Stump 2001, among others). By and large, in
such models the lexicon is the locus of richer structure (networks of related
inflected and derived words) and greater explanatory force than is assumed
in theories where the lexicon is simply viewed as a repository of listed
elements.
Sociality:
WS and autism
Miklós
Győri:
Fractionating 'theory of mind': evidence from autism. An overview
ELTE,
Institute of Psychology, Autism Foundation, Budapest
.Clinical
picture of Williams syndrome (WS) involves high level of sociability, in
sharp contrast to autism (autistic spectrum disorders; ASD). Recent studies,
however, suggest that 'theory of mind', the highly complex human cognitive
capacity to attribute mental states to agents, shows a specific pattern
of relative impairment in individuals with WS. These findings render research
on theory of mind functioning in ASD especially relevant in the context
of WS, since marked impairment of theory of mind is well documented in
ASD, as well as its causal role in the variety of social difficulties observable
in these syndromes.
Empirical
studies on theory of mind functioning in ASD revealed a considerable variety
in the pattern, degree and developmental changes in theory of mind impairment.
These results – in line with others from neurotypical subjects – suggest
that typically functioning theory of mind capacity is underlain by multiple
neurocognitive systems that may dissociate from each other in atypical
development.
The present contribution overviews and evaluates
the most important evidence from ASD for such dissociations, focusing on
the following issues:
-
Theory of mind capacity
and the variety of social behaviours
-
Competence and performance
in theory of mind functioning
-
Components of theory
of mind competence
-
Developmental patterns
and ways of compensation
Zsuzsa Káldy:
What mechanisms
affect the unusual social profile of Williams Syndrome individuals?
Rutgers, Department of Psychology
with Alan Leslie
Individuals with Williams Syndrome (WS) show an
unusual pattern of social behavior. They are overfriendly and outgoing,
and their language use is notably affective (Bellugi et al, 1998). These
characteristics are the opposite of what we find in autism, where one of
the core deficits is in mentalizing (Theory of Mind, ToM). However, WS
individuals are not super-mentalizers: they also have some serious social
difficulties. In terms of age groups, infants and toddlers do not follow
the gaze of others (joint attention), children cannot establish contact
with their peers, and in experimental situations (ToM tasks) WS adults
do not always reach the level of normal children. We hypothesize that what
is spared in WS is a paradoxical “conversational module”. A similar phenomenon
was found in a case of spina bifida many years ago by Cromer. The mechanism
of ToM might be independent from this module.
Determinants
of development in WS (Public Session)
Ursula
Bellugi, Edward S. Klima:
Linking Cognitive Neuroscience and Molecular Genetics:
New Perspectives from Williams Syndrome
Laboratory
for Cognitive Neuroscience, The Salk Institute for Biological Studies,
La Jolla, CA
Introduction
to Williams Syndrome Recent major advances in cognitive neuroscience,
in brain imaging and molecular genetics make this an ideal time to begin
to examine the links between these levels through the study of specific
genetic syndromes. We present an historical approach which contrasts different
genetically based disorders such as Williams syndrome with others such
as Down syndrome. Williams syndrome is a rare genetically-based disorder
resulting in a fascinating and puzzling profile of peaks and valleys of
abilities. Starting at a point in time where little to nothing was
known about the syndrome, we will show how initial studies have found that
the syndrome results in specific dissociations in higher cognitive functions,
both within and across domains: a) cognitive deficits but relative
strength in language; b) extreme disorders in spatial cognition but strength
in face processing; as well as c) hypersociability. Studies of cognitive
functions, brain structure, brain function, and molecular genetics resulting
from such syndromes can thus help begin to forge links between disparate
levels, including brain, gene, and cognition.
Neurobiological
Findings Contrasting Genetic Syndromes. We will present initial findings
from studies of Williams syndrome involving cognitive, neuromorphological,
neurophysiological, brain cytoarchitectonic and genetic probes. The
neuromorphological characterization of Williams syndrome using quantitative
high resolution voluming of magnetic resonance images (MRI) suggests that
there are differential areas of brain development in two contrasting genetic
syndromes. Although cerebral volumes are smaller than normal in both
Williams syndrome and Down syndrome subjects, anterior brain volume and
limbic structure volume appear proportionately better preserved in Williams
syndrome, and neocerebellar volumes are actually enlarged. Primary auditory
areas also appear to be disproportionately large in Williams syndrome subjects,
compared to Down syndrome and normal controls, perhaps subserving relative
strengths in language and affinity for music. We will present results of
initial studies in language, face, and space processing that provide clues
to neurophysiological phenotypic markers in Williams syndrome.
Summary:
These
studies may in the long run provide new clues to the neurobiological basis
of domains of higher cognitive functioning. The finding that specific
brain regions are selectively preserved and impaired in diverse genetically-based
syndromes suggests that they may come under the influence of specific genetic
developmental factors, or that their development is mutually interactive.
Such issues linking cognitive phenotypes, neural systems and molecular
genetics may have implications for cortical plasticity, and are important
to central questions of cognitive neuroscience.
Annette
Karmiloff-Smith:
Genotype
Phenotype Relations:
Why a Cognitive Developmental Perspective is Crucial
Institute
of Child Health, London
I will discuss three reasons why genotype/phenotype
mapping is not straight-forward even in a genetic disorder where the deleted
genes and the pattern of behavioural impairments have already been identified.
The case of Williams syndrome (WS) serves as a model. First, genotype/phenotype
relations will be discussed with respect to older children and adults with
WS, compared to non-WS individuals with similar but smaller deletions on
chromosome 7q11.23. Our studies suggest that it is at the level of underlying
*cognitive* processes, and not behavioural outcomes, that genotype/phenotype
relations must be explored. Second, I will show how even in domains.
Where people with WS score in the range of normal
controls, the cognitive processes they use are different. Third, I will
argue that it essential to consider genotype/phenotype relations in early
infancy and not solely in the phenotypic outcome. The infant brain is not
like a Swiss army knife, simply handed down by evolution with preformed,
specialized components that may be individually impaired at birth. Rather,
subtle impairments early on can have a differential impact on different
domains in the phenotypic outcome. Ontogenetic development itself is the
clue to understanding developmental disorders and their relation to the
structure of the adult cognitive system.
Visual
organization in WS
Janette
Atkinson:
Visuo-Spatial Cognition, Attention And Frontal Function In WS Children
University College London, Department of Psychology
With Oliver Braddick, Shirley Anker, Marko Nardini
Visual information is processed in two main brain
circuits (streams) called the ‘ventral’ (for discriminating between objects
and recognizing faces - who? what?) and ‘dorsal’ (for analyzing relative
motion and position in space to generate actions - where? how?). Our studies
with young individuals with WS has led us to the general hypothesis of
‘dorsal stream vulnerability’ where certain brain circuits, within the
parietal and frontal lobes together with the cerebellum, develop atypically.
Support for this model comes from our studies with a large number of WS
individuals (N =120) across a wide age range (9 months to 16 years), from
multiple measures of vision (including stereopsis for depth perception)
and spatial cognition e.g. tests to separate dorsal and ventral stream
function (block construction matching and copying, adaptation of Goodale
post-box task, motion and form coherence thresholds) and frontal lobe function
(counter pointing, Piagetian object permanence ‘A not B with delay’, Russell
Box task, Diamond’s Day/Night verbal ‘Stroop’, motor planning tasks). We
find performance divided between WS individuals who have difficulties on
both verbal and visuospatial tasks and those with difficulties only on
spatial tasks. Remarkable variability within and across individuals across
tests is a common feature, including general problems of attention in most,
but not all, WS children. These attentional difficulties are of particular
importance for educational/ intervention schemes. We discuss possible brain
underpinnings of these intra and inter individual differences in relation
to spatial and attentional tasks.
Methods:
We report initial findings on (a) a virtual reality navigational task,
in which children locate objects following spatial reorientation (adapted
from a task of O’ Keefe and Burgess to test adult hippocampal function).
We link results to our earlier findings on spatial planning. (b) 4 subtests
of the TEACh battery (‘Test of Everyday Attention in Children’) comparing
function of different attentional systems (for auditory sustained attention,
visual search and inhibition of a prepotent response).
Results:
In the virtual reality task, two inter-related difficulties have been identified;
the ability to switch between spatial representations at different locations
and to translate 2D into 3D spatial representations. On TEACh, WS individuals
(aged 5-14 years) show a varying degree of delay across all tests, with
the auditory, sustained attention, monitoring task more difficult than
tests of selective attention (involving pattern matching). Relative differences
in difficulty may depend on particular test material, the modality used
and /or memorial or temporal factors.
Discussion:
In the light of these new results we reconsider and refine the ‘dorsal
stream vulnerability’ model and address the potential use of such tasks
as educational and strategic training games to aid WS individuals in everyday
life.
Ilona
Kovács:
Low-level
Perceptual Deficit in Williams Syndrome
Rutgers Department
of Psychology
With Á.
Lukács, Á Fehér, M. Racsmány, Cs. Pléh
The
most severe volumetric changes in the WMS brain are found in the occipital
lobe, as measured by gross anatomical techniques (Reiss et al, 2000). Occipital
involvement is indicated also by cytoarchitectonic measurements: while
most cortical areas appear relatively normal, signs of abnormal neural
connectivity have been discovered in area 17 (Galaburda & Bellugi,
2000). These anatomical findings seem to call for studies addressing early
levels of visual processing in WMS.
We
studied early visual cortical processing in WMS by employing an orientation
discrimination, and a contour integration task. The orientation discrimination
task involves judgments about the spatial arrangement of simultaneously
presented pairs of Gabor signals, and it is assumed to be mediated by relatively
local, short-range spatial interactions. The contour detection task involves
the detection of a closed chain of high contrast Gabor signals embedded
in a random background of Gabor signals, and it is believed to be mediated
by long-range spatial interactions. Typically developing children show
an extended developmental period in their ability to integrate orientation
information across the visual field in both tasks (Nolan and Kovacs, 2002;
Kovacs et al, 1999). WMS subjects in our study lag behind typical age-norms,
and never reach typical adult performance levels. Some WMS subjects also
deviate from the normal pattern of results in orientation discrimination,
presenting the lack of the “oblique effect.” These results support the
possibility of abnormal spatial interactions and neural connectivity in
WMS visual cortex. The correlation between anatomical and behavioral data
in this case opens up a new dimension in the understanding of the neuroperceptual
profile in WMS; and it predicts that WMS subjects will encounter difficulties
in tasks involving both short-range and long-range interactions, and contextual
integration.
Katarina
Jariabková:
Visuo-constructive
abilities in individuals with Williams syndrome and Down syndrome as assessed
by Rey-Osterrieth Complex Figure
Department of Social and Biological Communication,
Slovak Academy of Sciences
With V. Bzdúch 2, M. Koš? 3,
M. Šustrová 4
2First Department of Pediatrics, University Children’s
Hospital,
3Department of Psychology, Trnava University, 4Institute
of Preventive and Clinical Medicine, Bratislava, Slovakia
Visuo-constructive impairments in copying and free
drawings have been reported in both Williams syndrome (WS) and Down syndrome
(DS). Qualitatively, productions of subjects with WS often show poor cohesion
and lack overall organization (cf. Wang et al., 1995; Bellugi et al., 2000).
The copy task of the Rey-Osterrieth Complex Figure
(ROCF) permits an analysis of performance accuracy as well as of the drawing
procedure (Osterrieth, 1944). The purpose of the paper is to present productions
of WS and DS subjects in the ROCF and to discuss the use of the test as
a tool for assessing the visuo-constructive abilities in WS.
The task was administered to 20 WS subjects (mean
age 16;10, range 7 to 33 years) and 12 DS subjects (mean age 17;7, range
7 to 28 years). The accuracy scores of all WS subjects and of most of the
DS subjects (83%) fell below the 10th percentile of developmental norms.
However, 2 DS subjects performed within the average range of the norms.
Types of drawing procedures with little or no organization were observed
in subjects from both groups. Three of the DS subjects (25%) demonstrated
developmentally higher procedures typical of normal adults. No WS subject
reached this level.
The data indicate more severe impairments in the WS
group and point to possible differences in performance with regard to the
way of administration of the test.
WS
and working memory
Chris
Jarrold:
Causes
and consequences of poor visuo-spatial short-term memory in Williams syndrome
Bristol
University, Department of Psychology
Individuals
with Williams syndrome perform poorly on tests of visuo-spatial short-term
memory, such as the Corsi span task, in which participants have to reproduce
spatial sequences in correct serial order. In our work my colleagues and
I have explored possible causes of this apparent problem, and in particular,
have asked whether individuals with Williams syndrome suffer from a fundamental
impairment to a specific visuo-spatial short-term store. In fact our evidence
to support this view is mixed, and it remains unclear whether people with
Williams syndrome have poorer visuo-spatial short-term memory than one
would expect given their general problems in the visuo-spatial domain.
In an alternative approach to this issue we have examined performance in
domains that one might expect to be affected by a visuo-spatial short-term
memory deficit. Although we find no evidence of particular problems in
learning visuo-spatial associations, we have found evidence of impaired
comprehension of spatial descriptions in Williams syndrome. This deficit
might result from an underlying visuo-spatial short-term memory problem,
but alternative explanations of this finding will also be discussed.
Mihály
Racsmány:
Dissociated components of working memory and their effects on long-term
acquisition in WS
SZTE Szeged
With Á.
Lukács, Cs. Pléh, I. Kovács
In the past
decade Williams syndrome (WS) has been linked to a cognitive profile characterized
by relatively preserved language abilities and seriously injured spatial
cognition (see Bellugi et al., 2000). One candidate as a background mechanism
for diverging verbal and spatial abilities is a multi-component working
memory system (Baddeley, 1986). Jarrold et al (1999) found dissociated
working memory performance in WS with a relatively preserved verbal and
an impaired spatial short-term memory capacity. Grant et al (1997) found
strong relationship between WS children's verbal working memory and language
performances.
In four experiments
we tried to test the effect of working memory capacity on long-term verbal
and spatial acquisition. In Experiment 1 we replicated the result of Jarrold
et al (1999) as we found dissociated verbal (digit span) and spatial (Corsi
blocks) working memory capacities in WS children comparing their performance
to control groups matched either on verbal or spatial mental age. In Experiment
2 we investigated the relationship between verbal working memory capacity
and productive vocabulary knowledge. According to our results, verbal working
memory span is a much stronger predictor of vocabulary knowledge in WS
than in the control group matched on verbal mental age. In Experiment 3
we tested WS children's spatial learning abilities using a repeated localization
task (Rey 5/25) and a map-route learning task. We found evidence that WS
children show impaired spatial learning on both tasks compared to control
groups matched on spatial mental age (block design) and their learning
performance was predictable by spatial working memory capacity. Finally,
in Experiment 4, similarly to Jarrold et al (in press), we found spatial
language difficulties using productive tasks and this performance was influenced
both by verbal and spatial working memory capacities. Our results support
a view that individual differences in working memory capacity constrain
the rate and speed of long-term acquisition of verbal and spatial information.
Methods
Measuring vision Memory measures and neuropsychology
Gábor
Pogány:
Foster the development of self–help consciousness in families of WS children
by interacting with researchers
Semmelweis
Med University, Budapest and Hungarian Williams Syndrome, Association
We want to
present the activity of the Hungarian Williams Syndrome Association, introducing
our specialties and the main differences between our organization and the
other similar associations in the western countries.
Because of
the lack of appropriate state education and health care system, we need
to undertake several functions of the government. Therefore, we need to
organize „gap-filling” services like hydrotherapeutic and rehabilitation
gymnastic (HRG) and sensomotor training, special educational therapy, music
and art therapy, special language and music teaching. The basis of our
programs is the good connection and fruitful cooperation with professionals
and researchers. A demonstration of our regular programs will be held ensuring
the possibilities of communication between parents and the participating
researchers.
We have some
good collaboration with WS investigators. For example, ours is the first
psychological study aiming at the characteristics of cognitive mechanisms
of WS children in Hungary. The neuropsychological methods developed by
the researchers can also introduce new diagnostic tools for handicapped
children.
Results will
hopefully open new possibilities of training and rehabilitation: locating
the specific deficit within the cognitive domain is the first step in choosing
or developing the appropriate rehabilitative method. We would also like
to draw attention to the educational and psychological problems WS children
and their families have to face.
The Hungarian
Williams Syndrome Association is happy to further help the parents and
teachers with new information based on psychological testing of the children.
Most importantly, by informing teachers about the specific peaks and valleys
in the cognitive and behavioral profile of WS people. We might facilitate
the development of more differentiated teaching methods in a classroom
of mentally retarded children using new information of their learning abilities
in different domains.
Chris
Jarrold:
Methods of assessing short-term and working memory
Bristol University, Department of Psychology
In this discussion of methodological approaches
I will outline ways of assessing short-term and working memory. In addition,
I will attempt to show how methodological considerations arise from three
particular theoretical assumptions.
1.that
working memory differs from short-term memory in terms of processing requirements,
2.that
verbal short-term memory performance is closely linked to language ability,
and
3.that
visuo-spatial short-term memory might fractionate into separate visual
and spatial subcomponents.
This material is based upon work supported by
the National Science Foundation under Grant No. 0126158. Any opinions,
findings, and conclusions or recommendations expressed in this material
are those of the author(s) and do not necessarily reflect the views of
the National Science Foundation.