INTERMANUAL DIFFERENCES ON MOTOR AND PSYCHOMOTOR TESTS IN ALCOHOLICS - NO EVIDENCE FOR SELECTIVE RIGHT-HEMISPHERE DYSFUNCTION

Some previous studies have suggested that alcoholics exhibit selective right, hemisphere dysfunction, based on alcoholics' poor performance on rests believed to subserve the right hemisphere. However, some of t hese experiments did not account adequately for differences in difficu lty or novelty in putative right hemisphere tasks. This experiment was designed to evaluate and compare intermanual differences in grip stre ngth, motor speed, fine-motor dexterity, and nonverbal problem-solving ability in 93 recently detoxified alcoholics, 54 long-term abstinent alcoholics, and 73 nonalcoholic controls. All subjects were right-hand ed men, matched for age and education, and both alcoholic groups had s imilar drinking histories. Using percent difference scores to assess i ntermanual differences, adjusted for demographics where appropriate, w e found that, although recently detoxified alcoholics demonstrate some motor and psychomotor impairments, there is no evidence using these t ests to suggest the right hemisphere is selectively more vulnerable to the effects of chronic alcohol abuse.