Non-mnestic cognitive function in the scopolamine model of Alzheimer's Disease

Abstract

The contribution of cholinergic dysfunction to the non-mnestic cognitive impairments associated with senile dementia of the Alzheimer type (SDAT) was investigated. Scopolamine (0 . 5 mg) was administered intravenously to 12 healthy individuals, and their performance on selected subtests of the Wechsler Adult Intelligence Scale Ð Revised (WAIS-R), and on additional non-mnestic neuropsychological tests were compared to that of 12 healthy control participants. The results demonstrate that scopolamine does impair performance on components of the WAIS-R, but that the Fuld WAIS-R pro®le does not have a cholinergic basis. Scopolamine did not impair performance on verbal¯uency, the Token Test, Judgment of Line Orientation, ®nger tapping, the Modi®ed Card Sorting Test, or the Mini-Mental State Examination. The results do not support the hypothesis that the cholinergic system contributes to the non-mnestic impairments in SDAT. #

Why people see things that are not there: A novel Perception and Attention Deficit model for recurrent complex visual hallucinations

“…Effects of cholinergic antagonism in many aspects of vision have been reported, including visual acuity, tracking performance, stereopsis, and spatial localisation (Caldwell et al 1992;Fisher 1991;Kobrick et al 1990;Meador et al 1993;Mentis et al 2000;Nobili & Sannita 1997;Penetar et al 1988). In addition, cholinergic antagonists impair performance on simple and complex visual recognition and visual spatial tasks (Bentley et al 2004;Dalley et al 2004;Flicker et al 1990;Meador et al 1993;Obonsawin et al 1998).…”

Believing is seeing in schizophrenia: The role of top-down processing

“…Impaired performance on virtually all tests of alertness and attention following reduced cholinergic function is well established (reviewed by Beelke & Sannita 2002;Collerton 1986). In addition, cholinergic antagonists impair performance on simple and complex visual recognition and visual spatial tasks (Bentley et al 2004;Dalley et al 2004;Flicker et al 1990;Meador et al 1993;Obonsawin et al 1998). In addition, cholinergic antagonists impair performance on simple and complex visual recognition and visual spatial tasks (Bentley et al 2004;Dalley et al 2004;Flicker et al 1990;Meador et al 1993;Obonsawin et al 1998).…”