Referential communication by aphasic and nonaphasic adults.

Nonaphasic and nonfluent, mixed, and anomic aphasic adults participated in a referential communication task in which they described pictures to a nonaphasic listener so that the listener could point to the picture being described from an array of four. Both aphasic and nonaphasic subjects were able to determine what information was crucial for identifying pictures and communicate that information to a listener. The major differences between nonaphasic and aphasic subjects were in efficiency and accuracy of communication. Nonaphasic and nonfluent aphasic subjects were more efficient in communicating information than mixed or anomic aphasic subjects were. Nonfluent aphasic subjects were as efficient as nonaphasic speakers in this respect. Aphasic subjects communicated significantly more inaccurate information than nonaphasic speakers did. However, no more than 5% of the information communicated by aphasic subjects was inaccurate. Finally, aphasic speakers modified their descriptions in response to apparent communication failure in the same way that nonaphasic speakers did.