Cognitive Heterogeneity in Williams Syndrome

Abstract

This study used the Woodcock-Johnson Tests of Cognitive Ability-Revised to investigate a wide range of cognitive abilities in people with Williams syndrome (WS). It involved a comparatively large sample of 31 people with WS, but took a case-series approach. The study addressed the widespread claims of a characteristic "WS cognitive profile" by looking for heterogeneity rather than homogeneity. People with WS showed a variety of preserved (significantly above mental age [MA]), expected (at MA), and significantly impaired (significantly below MA) levels of functioning. Such results provide clear evidence for heterogeneity in cognitive functions within WS. We found the most homogeneity on a test of phonological processing and a test of phonological short-term memory, with half of the WS sample performing at MA levels on these tests. Interestingly, no WS individual showed a weakness on a test of nonverbal reasoning, and only one WS individual showed a weakness on a test of verbal comprehension. In addition, we found that strengths on analysis-synthesis and verbal analogies occurred only for WS individuals with an MA less than 5.5 years (our sample median MA); people with an MA greater than 5.5 years performed at MA level on these 2 tests. Results also provided preliminary evidence for distinct subgroups of WS people based on their cognitive strengths and weaknesses on a broad range of cognitive functions. On the basis of the findings, caution should be made in declaring a single cognitive profile that is characteristic of all individuals with WS. Just as there is heterogeneity in genetic and physical anomalies within WS, not all WS individuals share the same cognitive strengths and weaknesses. Also, not all WS individuals show the profile of a strength in verbal abilities and a weakness in spatial functions.

Linking social behaviour and anxiety to attention to emotional faces in Williams syndrome

“…As hypothesised, levels of elevated anxiety in WS, specifically generalised anxiety were associated with reduced fixation to the eye region and prolonged fixation to the mouth region of fearful faces. These findings extend previous studies which have demonstrated substantial heterogeneity in the social profile in WS (Jarvinen-Pasley et al, 2010;Hanley et al, in press;Porter & Coltheart, 2005), and suggest that heightened anxiety may influence attentional allocation and avoidance processing of socially meaningful stimuli in some individuals with WS.…”

Heterogeneity of social approach behaviour in Williams syndrome: The role of response inhibition

“…These findings support studies which have demonstrated heterogeneity in WS (Järvinen-Pasley et al, 2010;Porter et al, 2007;Stojanovik, Perkins & Howard, 2006;Porter & Coltheart, 2005). Interestingly there was variability in age and IQ within clusters, indicating that developmental variables did not consistently or reliably predict RUNNING HEAD: Social Approach in Williams syndrome 19 SAB profiles.…”

“…Many developmental disorders are heterogeneous (Abrahams & Geschwind, 2008) and this is a particularly pertinent feature of WS, with cognitive, social, genetic and physical characteristics varying considerably from one individual to the next (Porter & Coltheart, 2005). Porter and Coltheart, (2005) challenged the notion of a "syndrome specific" (Howlin, Davies & Udwin, 1998) WS cognitive profile and suggested that subgroups might exist within WS based on their similarities in cognitive profile. They discovered evidence for two groups differing in terms of perception, attention and spatial construction abilities and differences in social-emotion skills.…”

Attentional lapse and inhibition control in adults with Williams Syndrome

“…Perhaps not surprising given predictable large individual differences within neurodevelopmental disorders, indeed considering the cognitive heterogeneity we 14 know to be associated with WS (Porter, & Coltheart, 2005) the hit rate was low (48% WS vs 93% CA vs 79% over 65yrs) and the standard deviation was high (28%). Regarding our analysis of variability in response times during the duration of the task it is evident that WS participants were unable to exert controlled processes to maintain focus during the task.…”

“…Individuals with the disorder tend to function within the mild-moderate range of intellectual difficulty (Searcy et al, 2004) and exhibit a cognitive profile of relative proficiency within the verbal compared to the nonverbal domain (Bellugi, Lichtenberger, Mills, Galaburda, & Korenberg, 1999). The cognitive profile of the disorder has attracted the attention of cognitive scientists for the last two decades due to this juxtaposition of relatively better verbal than non-verbal skill, but it is critical to emphasise that heterogeneity of cognitive function occurs (Porter, & Coltheart, 2005) and the relative difference between verbal and spatial skill co-exists against a background of mild-moderate intellectual difficulty. Within the cognitive profile, research has recently highlighted the importance of exploring the area of executive functioning (e.g.…”