Fogarty, Jennifer Noelle.2006-07-282006-07-2820012001http://hdl.handle.net/10012/681Research reviews have repeatedly concluded that cognitive and motor skills are not equally impaired by a moderate dose of alcohol, but they disagree on which type of task is more impaired. T he difficulties in comparing the effect of alcohol on cognitive and motor skills encountered in reviews of the literature underscore the need for research specifically designed to address this question. This thesis presents the results of two experiments designed for this purpose. This research used a within subject design in which the same person performed a pursuit rotor (PR) motor skill task and a cognitive rapid information processing (RIP) task requiring no learned motor skill. The pair of tasks was performed in counterbalanced order within each group. Tests on the pair of tasks occurred at intervals as blood alcohol concentration (BAC) rose and declined. In the first study, twenty male social drinkers received either a moderate dose of alcohol (0.62 g/kg) or placebo and performed the tasks under standard conditions that provided no consequence for performance. On both tasks, the alcohol group was significantly more impaired than the placebo group. Impairment in PR performance tended to increase and decline in accord with the blood alcohol curve, whereas the degree of impairment on the RIP task was unrelated to the blood alcohol curve. The second study tested the consistency of these two profiles of impairment in different environmental contexts by manipulating reinforcement for task performance. Four groups of social drinkers (N = 56) performed the tasks in the context of different reinforcement conditions. Reinforcement (25 cents reward) per test score under alcohol that was comparable to a drinker's drug-free score was administered either for both tasks, or only the motor, or only the cognitive task, or neither task. Rewarding the performance of a task under alcohol reduced the degree of impairment displayed, but the two types of tasks continued to show consistently different profiles of impairment as BACs rose and declined. On the motor task, impairment increased and diminished in accord with rising and declining BAC, whereas the degree of impairment on the information-processing task was not related to these BACs. The results imply that the controversy over which type of task is more impaired by a moderate dose of alcohol may be resolved by a consideration of the position on the BAC curve when performance is tested. Practical implications of the findings and their relevance to theories of acute behavioural tolerance to alcohol are also considered.application/pdf8713049 bytesapplication/pdfenCopyright: 2001, Fogarty, Jennifer Noelle.. All rights reserved.Harvested from Collections CanadaDoctoral Thesis