Abstract
We compared the discourse performance of 15 patients with early stage Alzheimer's disease (AD), 15 matched controls (NC), and 15 patients with mild to highly-moderately severe aphasia (AP). A single-frame picture description task and a procedural discourse task were used to elicit discourse. The stimulus picture was created to enable the subjects to produce inferential statements. In order to develop a new analytical system that could delineate clinical profiles of discourse in patients with AD, our analysis of discourse focused on qualitative characteristics, i. E. responsiveness, understanding task requirements, coping strategies for the task, and drifting away from the task, as well as information content. The content of information included the following : the people's behavior, climate, inferred information, and topic of the picture for the picture description task, and the explanation in an organized fashion of the steps necessary in a procedure for the procedural task. All of the participants were able to respond to the task instructions. Significant differences were revealed between the AD and NC groups for the majority of the items in the analysis. Some of the patients with AD exhibited difficulties in understanding the task requirements, poor coping strategies, and drifting away from the task. They also obtained lower scores on people's behavior, climate, picture topic, and explanation of the necessary steps of a procedure in an organized fashion. The AP group differed significantly from the AD group with respect to the understanding of the task requirements and people's behavior, coping strategy, and drifting away from the task. We were able to delineate the characteristics of discourse in patients with AD who are in the early stages, using the new discourse analysis system. The results are discussed in relation to the qualitative differences in discourse among the subject groups.
