Caffeine influence on the motor steadiness battery in neuropsychological tests.

Caffeine is a widely used drug with various biological effects. The present investigation focuses on a possible influence of caffeine upon motor steadiness performance in tests routinely used in neuropsychological testing. Twenty-four healthy females between 23 and 38 years were investigated in a randomised double-blind crossover study. A significantly poorer motor steadiness performance was found after ingestion of 300 mg of caffeine as compared to a placebo (decaffeinated coffee). Both error time and error count were increased after caffeine consumption. Caffeine also tended to reduce maze coordination test performance. We conclude that caffeine intake preferably should be avoided before neuropsychological testing of motor steadiness.