Error patterns in auditory comprehension of adult aphasics

The error patterns of normal and aphasic adults on a sentence comprehension test were studied. For position of error, both normals and the three aphasic groups performed consistently with the expected error distribution. Neither sentence half was experienced as more difficult to process. All groups, both aphasic and normal, demonstrated error patterns for grammatical class and for surface structure linguistic constituent which were consistent with the expected error distributions. Exceptions were noted for the normals on the verb class and for the Wernicke's aphasics on the NP and VP linguistic constituents. Rank orderings of error proportions were similar across groups for both grammatical form class and linguistic constituent. The general findings lend support to the notion that, for auditory comprehension of sentences, aphasic patients differ quantitatively from normal adult speakers, but behave qualitatively similar to them.