Proceedings of the Annual Meeting of the Cognitive Science Society

Individuals with Williams Syndrome (WS) display an unusual cognitive profile with severe deficits in spatial skills along with fluent and arguably complex language. Our experiment focused on the comprehension of scalar expressions, such as `some', `two', and `or' as a window to study their semantic and pragmatic competence. We compared performance of individuals with WS (mean age = 16,4 (year, month), age range = 11,10-21,11) to children matched by Mental Age (MA, (mean age = 6,1, age range = 5,2-7,8) and typical adults. No differences between the WS and MA groups were found in their knowledge of truth conditions of scalar terms. We further tested whether participants accept the statements with scalar terms in contexts featuring their logical (semantic) readings. Individuals with WS accepted logical readings more often than children matched by MA, suggesting that individuals with WS have access to the abstract meaning of scalar expressions.