Habilidades linguísticas em Síndrome de Williams: relações entre domínios linguístico e cognitivo visuo-espacial

Abstract

Williams-Beuren syndrome (Williams, 1961, Beuren, 1962) is characterized by the deletion of several genes from chromosome 7 that leads to distinctive physical signs. With their small and upturned nose, big lips, small teeth and frequent smiling (SILVA, 2008), the individual with Williams Syndrome (WS) presents an average intelligence quotient that is considered low (55, with normal value being 100) thus qualifying as intellectually disabled. In terms of cognitive deficits, visual-spatial disabilities are often reported and usually related to gene LIMK1 deletion. Concerning linguistic skills, the literature is conflicting: some authors state it is unaltered among these patients, who show an unusual and rich vocabulary (Bellugi et al, 1988, 1990, 1992, 1994; Reilly, Klima, & Bellugi, 1990), while other authors report these skills as impaired in WS individuals (Capirci, Sabbadini, & Volterra, 1996; Karmiloff-Smith et al., 1997a, b; Thomas et al., 2001; Volterra, Capirci, Pezzini, Sabbadini, & Vicari, 1996). This work focuses on the relation between linguistic skills and cognitive deficits, specifically visual-spatial disabilities in WS individuals, in the light of generative assumptions concening a model of language resulting from an innate Faculty of Language, which distinguishes the species (Chomsky, 1995). Aparent linguistic impairment in WS individuals can be taken as a reflex of their cognitive deficit, particularly associated to the visual-spatial skills, rather than a linguistic module impairment stricto sensu. It s then possible to assume that language in WS is preserved, from a modular point of view (Fodor, 1983). In order to investigate the relation between linguistic and visual-spatial modules, three tests were run: MABILIN, which evaluates linguistic comprehension in complex structures, and two other tests developed specifically for this investigation, which aim at evaluating spatial terms, one being focused on language comprehension and the second on production skills. The data obtained show inferior results for WS individuals compared to control group on tasks involving spatial terms, and similar results in tasks that involve complex language structures. Therefore, results seem to support the view that these individuals' computational system for language, responsible for linguistic expressions derivation, is preserved as well as their ability to identifying and retrieving general lexical items related to spatial and locative categories. Inferior outcomes related to sentences involving spatial terms demonstrate a cognitive deficit on domains that may affect the interface between the computational system and the integration between linguistic and extra-linguistic information.