Automatic access of lexical information in Broca's aphasics: against the automaticity hypothesis.

A number of recent articles have claimed that the language comprehension impairments of so-called agrammatic patients can be characterized as being due to problems with the automatic access of semantic and/or syntactic information from the lexicon. We describe three experiments, all using tasks which probe the immediate and automatic access of lexical information and compare the performance of agrammatic patients with that of an anomic and a fluent patient. We find no evidence in support of the automaticity hypothesis as an explanatory account of the language deficits of agrammatic aphasics. Further, we argue that current research does not lend itself to a single-explanation account of agrammatic comprehension problems, and that in-depth analyses of individual patients are more likely to be fruitful in terms of understanding the nature of comprehension deficits.