Determinants of sentence comprehension in aphasic patients in sentence-picture matching tasks.

The results of two studies of sentence comprehension in aphasic patients using sentence-picture matching tests are presented. In the first study, 52 aphasic patients were tested on 10 sentence types. Analysis of the number of correct responses per sentence type showed effects of syntactic complexity and number of propositions. Factor analysis yielded first factors that accounted for two-thirds of the variance in performance to which all sentence types contributed. Clustering analysis yielded groups of patients whose performances progressively deteriorated and in which performance was more affected by sentence types that were harder for the group overall. These results were very similar to those previously obtained using an enactment task. In the second study, 17 aphasic patients were tested on the same 10 sentence types using both sentence-picture matching and enactment tasks. Correlational analyses showed that performance on the two tests was significantly correlated across both subjects and sentences. The results provide data relevant to the determinants of the complexity of a sentence in auditory comprehension.