Semantic sensitivity for prose in patients with probable alzheimer's disease

This study examined the sensitivity of patients with probable Alzheimer's Disease (AD) to the inherent semantic structure of prose. Patients and normal controls listened to prose passages and recalled the stories under immediate and delayed conditions. Subjects were also tested with a recognition format. Unlike controls and patients with mild AD, patients with severe AD were unable to differentiate high importance ideas from ideas of lower importance on free recall and recognition. These results suggest relative impairment of semantic processing at the encoding and consolidation process of memory in more advanced AD.