Longitudinal effects of Alzheimer disease on discourse production.

As part of a 5-year study of the longitudinal effects of Alzheimer disease (AD) on language, discourse samples from three patients diagnosed with AD and three matched normal controls were analyzed. A picture-description task was used to elicit comparable samples of discourse. Subjects were asked to describe the "Easter Morning" picture by Norman Rockwell. Samples were tape recorded, transcribed, and scored using eight measures of discourse production. These measures successfully quantified the changes in quantity and quality observed in the discourse of AD patients over time. Results revealed remarkably similar patterns, adding a longitudinal dimension to the growing body of knowledge of the effects of AD on discourse production.