SPHS Colloquium

You are cordially invited to attend a colloquium presented by the SPHS Department and the SPHS PhD Organization.

Dr. David Kemmerer
Department of Speech, Language, and Hearing Sciences and Department of Psychological Sciences Purdue University

Monday, March 22, 2010
4:00 – 5:00 p.m.
Speech and Hearing Building, Room C141

BEHAVIORAL PATTERNS AND LESION SITES ASSOCIATED WITH IMPAIRED PROCESSING OF LEXICAL AND CONCEPTUAL KNOWLEDGE OF ACTIONS

Abstract:
To further investigate the neural substrates of lexical and conceptual knowledge of actions, we administered a battery of 6 tasks to 226 brain-damaged patients with widely distributed lesions in the left and right cerebral hemispheres. The tasks probed lexical and conceptual knowledge of actions in a variety of verbal and non-verbal ways, including naming, word-picture matching, attribute judgments involving both words and pictures, and associative comparisons involving both words and pictures. Of the 226 patients who were studied, 61 failed one or more of the 6 tasks, with 4 patients being impaired on the entire battery, and varied numbers of patients being impaired on varied combinations of tasks. Overall, the 61 patients manifested a complex array of associations and dissociations across the 6 tasks. The lesion sites of 147 of the 226 patients were also investigated, using formal methods for lesion-deficit statistical mapping and power analysis of lesion overlap maps. Significant effects for all 6 tasks were found in the following left-hemisphere regions: the inferior frontal gyrus; the ventral precentral gyrus, extending superiorly into what are likely to be hand-related primary motor and premotor areas; and the anterior insula. In addition, significant effects for 4-5 tasks were found in not only the regions just mentioned, but also in several other left-hemisphere areas: the ventral postcentral gyrus; the supramarginal gyrus; and the posterior middle temporal gyrus. These results converge with previous research on the neural underpinnings of actions words and concepts. However, the current study goes considerably beyond most previous investigations by providing extensive behavioral and lesion data for an unusually large and diverse sample of brain-damaged patients, and by incorporating multiple measures of verb comprehension.