Effects of scopolamine upon behavioral reactivity and visually evoked potential to flashes in rats.

Abstract

Examined the averaged visual evoked response (VER) at cortex and behavioral reactivity to photic stimuli in 21 male albino Holtzman rats following administration of varying dosages of scopolamine hydrobromide, scopolamine methyl nitrate, or saline. The pattern of behavioral and electrophysiological results with scopolamine paralleled earlier findings with septal lesions. The drug impaired habituation of behavioral reactivity of flashes and altered VERs in 2 ways that appeared to relate to the behavioral impairment. It augmented the positive component of the early negative-positive complex and produced a dissociation between the amplitude of the late negative wave of VER and behavioral activity. These effects are viewed in terms of ascending cholinergic arousal processes and interrelationships of arousal and behavioral patterns. (26 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved)