The effects of scopolamine and cyclizine on visual-vestibular interaction in humans.
The aim of the present study was to investigate the effects of scopolamine (1.5 mg, transdermal patch) and cyclizine (50 mg tablet), at the doses usually used for the relief of motion sickness, on postural sway, optokinetic nystagmus (OKN) and circularvection (CV) in humans, using a within-subjects, double-blind, placebo-controlled design. Scopolamine and cyclizine were found to have no significant suppressive effect on these aspects of visual-vestibular interaction. Postural sway and CV were not significantly affected by either drug treatment; OKN SPV was significantly increased (p < 0.05), although OKN amplitude and frequency were unaffected. These results suggest that scopolamine and cyclizine, at doses used for the relief of motion sickness, may have minimal suppressive effects on these aspects of visual-vestibular interaction.
Dept. of Psychology and the Neuroscience Research Centre, University of Otago, Dunedin, New Zealand.
J
J
Gowans
A
A
Matheson
C L
CL
Darlington
P F
PF
Smith
D000279:Administration, Cutaneous; D000328:Adult; D000360:Afterimage / Q000187:drug effects; D018680:Cholinergic Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D018592:Cross-Over Studies; D003501:Cyclizine / Q000494:pharmacology*; D004311:Double-Blind Method; D004585:Electrooculography; D006634:Histamine H1 Antagonists / Q000494:pharmacology*; D006801:Humans; D007088:Illusions / Q000187:drug effects; D008297:Male; D009039:Motion Perception / Q000187:drug effects*; D009041:Motion Sickness / Q000188:drug therapy; D017120:Nystagmus, Optokinetic / Q000187:drug effects*; D004856:Postural Balance / Q000187:drug effects; D011187:Posture; D011434:Proprioception / Q000187:drug effects; D011930:Reaction Time; D012601:Scopolamine / Q000008:administration & dosage / Q000494:pharmacology*
D018680:Cholinergic Antagonists; D006634:Histamine H1 Antagonists; D012601:Scopolamine; D003501:Cyclizine