Can Caffeine Boost Memory?

It’s debatable, but there is some evidence that caffeine may sharpen memory. Researchers at London’s National Addic­tion Centre tested 9003 adult caffeine users. Those who drank the most caffeine in coffee, and to a lesser extent in tea, performed best on a number of cognitive tests, includ­ing reaction time, verbal memory, and visual-spatial rea­soning, than non-caffeine users. Older people got more of a mental boost from caffeine than younger people, con­cluded investigators.

Dutch researchers also found that caffeine can boost memory. Researchers at the University of Limburg in Maastricht had sixteen persons take a drug that impaired short-term and long-term memory.

Consuming caffeine dramatically reversed the drug-induced impairment. Sub­jects who drank two to three small cups of coffee (250 mil­ligrams caffeine) retrieved information from their long-term memory and recalled words from short-term and long-term memory tests normally; their reading speed and visual searches also improved almost to the non-drug level. Re­searchers attributed the memory enhancement to a stimu-

lation of “cholinergic activity,” or increases in activity of the “memory” neurotransmitter acetylcholine, which happens, they say, when caffeine blocks adenosine.

Italian investigators also showed that caffeine improves memory consolidation in experimental animals, as shown by their enhanced ability to remember how to find their way through mazes. But caffeine improved memory through mechanisms other than by blocking adenosine, researchers concluded.

Another reason caffeine might boost memory: It causes a slight adrenaline rush that clears up fuzzy brains. Adren­aline also triggers a rise in blood sugar (glucose) which in turn prods increased release of the memory enhancing neu­rotransmitter, acetylcholine.

Dr. Richard Restak, of George Washington University and an authority on the brain, recommends the “judicious use of caffeine” to help older people compensate for the slowing down of brain functioning.

On one test, caffeine flunks. You can’t count on massive amounts of caffeine to improve your ability to make com­plex managerial decisions, according to tests at Penn State University. Researchers had twenty-four highly paid man­agers who normally consumed four or more cups of coffee daily (400 to 1000 milligrams of caffeine) take a six-hour video-computerized test of scenarios designed to test their skill at making complex managerial decisions.

A week later, the managers were told to take an extra 400 milligrams a day of caffeine in capsules. Although this is a lot of caffeine (bringing everybody’s intake up to eight to fourteen cups of coffee a day), it’s not unusual for peo­ple under stress to consume that much, said researchers. The subjects were then put through another simulated video-computer test of their complex managerial skills to determine whether they did better or worse.

Interestingly, under the influence of excess caffeine, they were 20 percent speedier in making decisions. But their decisions were not necessarily better. Indeed, the managers’ capacity to take advantage of specific opportunities, a good predictor of real-world managerial success, deteriorated on the excessive doses of caffeine—perhaps because the man­agers jumped to action without taking enough time to remember and consider information relevant to the deci­sion. In general, though, the excess caffeine had no impact on most measures of managerial effectiveness, researchers concluded.

Coffee, brewed: About 20 milligrams of caffeine per ounce.

Tea: About 5 milligrams of caffeine per ounce.

Cola: About 4 milligrams of caffeine per ounce.