Cognitive functioning in Williams syndrome : a study in Portuguese and Spanish patients

Williams Syndrome (WS) is a genetic neurodevelopmental disorder caused by a submicroscopic
deletion on chromosome 7 q11.23. This is a systemic disorder in which cardiac
problems and mental retardation are the key phenotypic symptoms. Although displaying
a general cognitive impairment, they are most often described as exhibiting a peak and
valley profile, with relative sparing of language and face processing abilities and severe
impairment of visual–spatial cognition. In this study, we conducted a detailed cognitive
assessment using Wechsler Intelligence Scales on a WS and a normal development control
group. To explore the hypothesis of a dissociative cognitive architecture in WS, performance
on subtests, factorial indexes and composite measures of Verbal, Performance
and Full Scale Intelligence Quotient were analysed. Individuals with WS were found to
score in Full Scale Intelligence Quotient (FSIQ) within mild to moderate mental retardation
interval, and had significantly lower scores in all measures when they were compared with
the normal development group. However, a specific intragroup cognitive profile was found
for Williams Syndrome (confirming Mervis’ definition of the WS cognitive profile) along
with a specific developmental pathway (absence of an age-associated cognitive decline).
Fundação para a Ciência e a Tecnologia (FCT)
This research was supported by the grants POCTI/PSI/58364/
2004 and SFRH/BD/16091/2004