The New York Times reports of a study of 61 people, where those who took a 2-hour afternoon caffeine or a placebo.did better at repeating verbal, perception, and motor-skill tests than those given
Those who had caffeine had worse motor skills than those who napped or had a placebo. In the perceptual task, the nappers did significantly better than either the caffeine or placebo group. On the verbal test, nappers were best by a wide margin, and the caffeine consumers did no better than those given a placebo. Despite their mediocre performance, caffeine takers consistently reported less sleepiness than the others.
â€œPeople think theyâ€™re smarter on caffeine,â€ said Sara C. Mednick, an assistant professor of psychiatry at the University of California, San Diego, and the lead author of the study, which appeared in the Nov. 3 issue of Behavioral Brain Research. â€œBut this study is a strong argument for taking a nap instead of having a cup of coffee.â€
The full study paper is available here: