Cerebral cortical somatostatin and cognitive dysfunction in Alzheimer's disease
This study investigated the relationship between cerebral cortical somatostatinergic activity and neuropsychological dysfunction in Alzheimer's disease. Somatostatin-like immunoreactivity was determined in frontal lobe cortical biopsy samples obtained from five Alzheimer's disease patients. Prebiopsy quantification of the following neuropsychological variables was performed: global cognitive decline; verbal, nonverbal and full-scale intelligence; verbal and visual memory; language; visual perceptual discrimination and organization; simple auditory, simple visual, and four choice visual reaction time; and attention and concentration ability. The association between cortical somatostatinergic activity and these various neuropsychological functions was explored via the calculation of Spearman's rank-difference correlation (Rho). Findings are discussed within the context of: (a) the so-called "cholinergic hypothesis" of Alzheimer's disease, and (b) recent reconceptualizations of Alzheimer's disease as a primary cortical disease.