LANGUAGE AND WILLIAMS-SYNDROME - HOW INTACT IS INTACT

It has been claimed that Williams syndrome (WS), a rare neurodevelopme ntal disorder, is characterized by serious cognitive deficits alongsid e intact language. The syndrome is often used as a prime example of th e modularity of an innate faculty for morphosyntactic rules. We challe nge this claim and hypothesize that morphosyntax, although surprisingl y good given WS level of mental retardation, is by no means intact. We make an initial test of this hypothesis through an analysis of the re ceptive language of a group of English-speaking WS individuals on a st andardized morphosyntactic test. We then present an experimental study of expressive language that examines grammatical,gender assignment in French-speaking WS patients. Despite a Verbal Mental Age selected to be higher than the chronological age of the young control group, these people with WS continue even in adulthood to show clear-cut deficits in their production of an aspect of morphosyntax that normal children acquire effortlessly very early. The results of the 2 studies, one foc using on receptive language and the other on expressive language, chal lenge the notion that comprehension and use of morphosyntactic rules i n WS individuals are intact. The within-domain dissociations regarding the use of grammatical gender assignment across several sentence elem ents and their difficulties in understanding embedded sentences-two qu intessentially linguistic skills-suggest that we must rethink the noti on of spared, modular, language capacities in Williams syndrome. We co nclude that WS language follows a different path to normal acquisition and may turn out to be more like second language learning.