Specific visuomotor deficits due to alcohol intoxication: evidence from the pro- and antisaccade paradigms.
BACKGROUND
Alcohol affects a variety of human behaviors, including visual perception and motor control. Although recent research has begun to explore mechanisms that mediate these changes, their exact nature is still not well understood.


OBJECTIVE
The present study used two basic oculomotor tasks to examine the effect of alcohol on different levels of visual processing within the same individuals. A theoretical framework is offered to integrate findings across multiple levels of oculomotor control.


METHODS
Twenty-four healthy participants were asked to perform eye movements in reflexive (pro-) and voluntary (anti-) saccade tasks. In one of two counterbalanced sessions, performance was measured after alcohol administration (mean BrAC=69 mg%); the other served as a within-subjects no-alcohol comparison condition.


RESULTS
Error rates were not influenced by alcohol intoxication in either task. However, there were significant effects of alcohol on saccade latency and peak velocity in both tasks. Critically, a specific alcohol-induced impairment (hypermetria) in saccade amplitudes was observed exclusively in the anti-saccade task.


CONCLUSIONS
The saccade latency data strongly suggest that alcohol intoxication impairs temporal aspects of saccade generation, irrespective of the level of processing triggering the saccade. The absence of effects on anti-saccade errors calls for further research into the notion of alcohol-induced impairment of the ability to inhibit prepotent responses. Furthermore, the specific impairment of saccade amplitude in the anti-saccade task under alcohol suggests that higher level processes involved in the spatial remapping of target location in the absence of a visually specified saccade goal are specifically affected by alcohol intoxication.
Vorstius
Christian
C
Department of Psychology, Florida State University, 1107 W. Call Street, Tallahassee, FL 32306-4301, USA.
Radach
Ralph
R
Lang
Alan R
AR
Riccardi
Christina J
CJ
D000328:Adult; D000435:Alcoholic Intoxication / Q000503:physiopathology*; D000704:Analysis of Variance; D001944:Breath Tests; D000431:Ethanol / Q000008:administration & dosage / Q000494:pharmacology*; D053483:Eye Movement Measurements; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation; D011597:Psychomotor Performance / Q000187:drug effects*; D011930:Reaction Time / Q000187:drug effects; D012438:Saccades / Q000187:drug effects* / Q000502:physiology; D014796:Visual Perception / Q000187:drug effects
D000431:Ethanol