It has previously been shown that 0.6 mg of scopolamine produces a delay in the flash visual evoked potential of young normal volunteers, while the pattern-reversal response does not change in latency. Recent work has shown that this drug differentially affects parvocellular and magnocellular systems. To investigate this effect, two studies were performed. In the first study, 0.4 mg of scopolamine was injected intramuscularly into 11 young, healthy male volunteers who had fasted overnight. The visual evoked potential was recorded to both binocular flash stimulation and monocular pattern-reversal stimulation by means of a checker-board consisting of 56' checks in a 28 degrees field. Responses were recorded before administration of the drug and then 1, 2, 4 and 6 hours after administration. The scopolamine produced a slowing of the flash P2 latency of approximately 6 ms (p < 0.05) two hours after drug administration. There was no effect on the latency of the flash N2 or pattern-reversal N75 or P100. There was an increase in amplitude of the flash N2-P2 component 6 hours after drug administration and an increase in the amplitude of the N75 and P100 2, 4 and 6 hours after the drug. Further subjects were investigated with the use of topical administration of 0.125% scopolamine applied monocularly. In all studies the other eye acted as a control. The subjects were again young healthy volunteers. The visual evoked potential was recorded to both flash and pattern-reversal stimulation with a checkerboard consisting of 60' checks counterphasing at 2 Hz within a 5 degrees field. Results suggest that systemic scopolamine affects the tectal pathway but has no peripheral effect.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.