Contextual influences in reading comprehension in aphasia.

Aphasic subjects' auditory comprehension of reversible passive sentences is facilitated by preceding predictive and nonpredictive narratives (Hough, Pierce, & Cannito, 1989, Brain and Language, 36, 325-334). The present study found that aphasic subjects also comprehended written reversible passive sentences significantly more accurately when they were preceded by either predictive or nonpredictive five-sentence narratives than when they were presented in isolation. Also tested was the contention that predictive narratives do not improve aphasic subjects' ability to process target sentences but simply allow these sentences to be ignored. This contention was not supported. The aphasic subjects did not comprehend predictive narratives presented without the subsequent target sentences more accurately than they comprehended the target sentences presented in isolation. For comprehension to be enhanced, both the contextual narratives and the target sentences must be present.