Alcohol and disorientation-related responses: VI. Effects of alcohol on eye movements and tracking performance during laboratory angular accelerations about the yaw and pitch axes

Abstract

Abstract : Alcohol ingestion interferes with visual control of vestibular eye movements and thereby produces significant decrements in performance at a compensatory tracking task during oscillation about the yaw axis; significant or consistent decrements in performance in the absence of motion were not obtained. The present study was designed to extend knowledge about these effects to pitch-plane stimulation. Alcohol doses were 2.0 ml of Smirnoff vodka per kg of body weight and tests were conducted before drinking and one, two, and four hours after drinking. In the absence of motion, there was no difference between the groups in tracking error while subjects were in the pitch position; significantly more errors occurred for alcohol subjects in the yaw position one and four hours (but not two hours) after drinking. During motion, one and two hours after drinking, alcohol subjects performed significantly poorer than the non-drinkers and had significantly less control of their eye movements for both axes of stimulation. Absolute error was greater during all sessions for pitch-plane stimulation as compared with yaw-plane stimulation. These degrading effects of alcohol on performance, particularly evident during motion, are discussed from the viewpoint of aviation safety. (Modified author abstract)