Effects of Broca's Aphasia and LIPC Damage on the Use of Contextual Information in Sentence Comprehension

Although widely explored, the nature of the lexical-semantic deficit observed in Broca's aphasia and its relation to the brain region of the same name has remained elusive. The present study coupled a case study approach with an auditory sentence-priming task to test hypothesized deficits in activation, selection, and integration mechanisms. Lexical decision latency and accuracy for three types of "Broca's" aphasic (one with damage to Broca's area and with a diagnosis of Broca's aphasia, one with damage to Broca's area but without Broca's aphasia, and one without damage to Broca's area but with Broca's aphasia) were compared to the performance of an aphasic patient with neither damage to Broca's area nor symptoms of Broca's aphasia. Results, however, did not clearly conform to predictions of any account, nor fall along traditional diagnostic or lesion criteria. Rather, the data indicated deviant patterns of controlled processing in all patients. It is argued that these discrepancies highlight certain common, but problematic, methodological practices in patient research, and alternative approaches are suggested.