Dr. Sheila Blumstein

Phonetic category structure and the mapping of sound structure to the lexicon: Evidence from lesion studies and functional neuroimaging

Friday, April 4, 2008 at 1:30 pm -3:30 pm
Room 1034, McIntyre Medical Building, 1200 av des Pins ouest

Dr. Sheila Blumstein is a an Alfred D. Mead Professor of Cognitive and Linguistic Sciences at Brown University

Abstract

The processes underlying both speaking and understanding appear to be easy and seamless. And yet, speech input is highly variable, the lexical form of a word shares its sound shape with many other words in the lexicon, and often a given word will have multiple meanings. The goal of this research is to examine how and in what ways the neural system is, on the one hand, sensitive to the variability in the speech and lexical processing system, and, on the other, is able to resolve this variability in determining phonetic category membership, lexical form, and word meaning. Evidence from studies of aphasia and functional neuroimaging will be examined with particular focus on categorical perception of speech, lexical competition, and meaning ambiguity in words. Results suggest that the processing of speech and lexical form recruits a distributed neural system that includes temporal, parietal, and frontal structures, and the processing of word meaning recruits temporal and frontal structures. The inferior frontal gyrus appears to play a domain general role across levels of the linguistic grammar in resolving variability not only of phonetic structure but also of phonological, lexical, and meaning competition.