Fun and Fitness for the 40-Something

It’s Friday, and you’re dragging at work (or at play)—what do you do? While a cat nap might be tempting, you’re probably more likely to hit Starbucks. Depending on your tasks, though, a nap might be just the ticket.

According to the National Institute of Mental Health (NIMH), 90 percent of North Americans use caffeine every day. While caffeine has been shown to enhance alertness and concentration, questions remained about its benefits for memory. Daytime napping, on the other hand, has been shown to increase alertness and promote learning on some memory tasks.

NIMH-supported researchers trained 61 participants in the morning on verbal memory, motor learning and perceptual learning tasks. After lunch, one group napped for 60-90 minutes. Two other groups listened to a book on tape and received a pill with either 200 mg of caffeine (a little less than a Tall Starbucks brewed coffee) or a placebo. Later in the afternoon, the three groups were tested to see how well they had learned the tasks.

Caffeine impaired motor learning and verbal memory, but an afternoon nap benefited all three types of learning. The nappers performed significantly better than the caffeinated group on a finger-tapping motor task and at recalling words. The nappers also beat both the caffeine and placebo groups on a texture discrimination task of perceptual learning. The placebo group performed better than the caffeine group on all three tasks. Interesting, merely knowing that the pill might contain caffeine helped as much as a nap on the motor task.

The results suggest that caffeine interferes with tasks that require processing explicit (as opposed to implicit) information. Caffeine, then, would interfere with a task like recalling a specific word or remembering what you learned at a tennis lesson—but not a task like remembering how to type or ride a bike.

“Such an impairment of performance runs counter to society’s assumption that caffeine typically benefits cognitive performance,” the lead researcher notes. “Apparent improvements with caffeine might actually reflect a relief from withdrawal symptoms. Just as no medicinal alternative to a good night’s rest has been discovered, so too caffeine, the most common pharmacological intervention for sleepiness, may not be an adequate substitute for the memory enhancements of daytime sleep.”

Now if only you could convince your boss to let you put your head down.

This entry was posted on Friday, December 19th, 2008 at 8:21 am and is filed under Health and Wellness. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.