Well blow me down! Popeye was right: Eat your spinach. It won't confer the bicep-bulging strength enjoyed by the famous cartoon sailor, but it may boost your brainpower slightly, suggests a small, preliminary study presented at a recent meeting of the Society for Neuroscience.

Spinach is rich in antioxidants, substances in fruits and vegetables thought to promote health in various ways. Researchers reported that laboratory rats fed a diet rich in spinach for seven weeks performed better on a test of learning and memory than rats fed on unfortified chow.

Can these results be extended to humans? We don't know yet. But the study is notable for having linked an antioxidant-rich diet directly to a memory-related task-namely, eye blink conditioning.

Rats fed on the antioxidant diet were quicker to learn that hearing a certain sound was always followed by a gentle puff of air in one eye. In response, rats shut one eye in anticipation of the puff-a conditioned response that requires memory. Previous studies showed that antioxidants have potentially beneficial effects on individual brain cells. The new work extends the connection from brain cells to brain function

In theory, antioxidants may counteract the effects of aging by neutralizing free radicals, which are molecules in the body that readily react with others. Produced as a normal part of metabolism, free radicals can damage cell membranes and cause other mischief thought to be part of the aging process. Oxidation, for example, may play a role in the progression of Alzheimer's disease. By defanging free radicals, antioxidants may have an anti-aging effect in the brain.