Caffeine enhances initial but not extended learning of a proprioceptive-based discrimination task in nonsmoking moderate users.

We examined the effects of caffeine on fine motor performance and learning using a multiple-force discrimination task. 93 college-aged subjects performed this task on which multiple measurements were made in an operant response paradigm. Quantitative measures of accuracy of response, duration of response, latency of response, force, and variability of force were examined. Significant interactions for caffeine dose by session on accuracy of response and latency of response indicated that caffeine enhanced the initial learning of a proprioceptive motor task but did not improve performance beyond that of normal practice.