Abstract
To investigate the semantic memory of aphasic patients, classification tasks were administered to Broca's, Wernicke's, Mixed aphasics, and normal adults in two experiments. The subjects were shown some drawings of various objects and asked to classify them into two conceptual categories.
If the semantic memory were impaired, the drawings would not be classified into conceptual categories well.
The aphasics classified them into conceptual categories less well than the normals. And the Mixed aphasics did less well than the Broca's and Wernicke's aphasics. The semamtic distance between the two categories in each task had an effect on all the aphasic groups, especially on the Wernicke's aphasics. The visual similarity between them had an effect on the Broca's and Mixed aphasics, especially on the Mixed aphasics.
The findings indicate that many aphasic patients have a disturbance in semantic memory.
