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Isolating deficits in linguistic knowledge

Trainee Achievements

Isolating deficits in linguistic knowledge

Language impairment research faces the fundamental problems of isolating deficits to particular components of linguistic knowledge and processing, and of statistically comparing impaired and unimpaired performance on a wide variety of experimental tasks. In work with core faculty members Brenda Rapp and Colin Wilson, trainee Mike Wolmetz has applied likelihood-based methods to quantify unimpaired performance on several speech perception tasks, and demonstrated that the performance on the same tasks of patient DMN differs systematically: DMN fails to show the categorical perception effect (anomalous or 'intermediate' speech sounds are perceived as members of known linguistic categories), and DMN differs in the effect of the word/non-word status of the stimulus. DMN’s impairment results from a left temporo-parietal infarct; these results suggest that processing of speech in the right hemisphere is both more gradient and more transient than corresponding processing in the left hemisphere.