Word-retrieval in aphasia: an investigation of semantic complexity.

Performance of aphasic subjects in adjective recognition and production tasks in which adjectives varied in semantic feature and markedness complexity was investigated. Twelve pairs of adjectives were examined in three experimental tasks; viz., picture recognition, antonym production, and sentence completion. Subjects were eight nonfluent and eight fluent aphasics. The results indicate significant differences in performance were dependent upon semantic features, markedness, experimental tasks, and type of aphasia. The discussion related semantic complexity to cognitive processes.