Knowledge of scripts reflected in discourse of aphasics and right-brain-damaged patients.

Script knowledge was examined in discourse produced by 15 mildly moderately impaired aphasics, 15 right-hemisphere-damaged (RHD) subjects. 15 neurological patients without central nervous system damage, and 30 normal controls. Experimental task were designed to elicit knowledge of particular scripts, various scripts from a category, metascripts, and plans. The results showed that the brain-damaged patients were able to produce information belonging to a given semantic category of scripts. Disorders demonstrated by both aphasics and RHD patients involved different discourse processes. Aphasics' impairment was mainly connected with discourse macroprocessing. Disturbances in the RHD subjects were found in text structures, contents, and macrostructure. The problem of the probable mechanisms of the observed discourse disturbances were discussed.