Effects of vocabulary, syntax, and sentence length on auditory comprehension in aphasic patients.

Summary Three groups of adult aphasics (Broca’s, Wernicke’s and amnesic) and a group of normal control subjects were compared on a test of auditory comprehension for sentences. The test sentences constructed varied systematically in the parameters of length, vocabullary difficulty, and syntactic complexity. The pattern of aphasics’ responses indicated that they differed from the normal controls in quantitative performance, but not in qualitative aspects. The aphasic subgroups varied in comprehension ability, with the Wernicke's patients performing the poorest. Syntactic complexity proved to be the most difficult parameter for all subjects. Comprehension of sentences of increased difficulty was significantly poorer than comprehension of easy sentences. Clinical applications of the test were discussed.