In a double-blind, placebo-controlled study, postmenopausal women (53-65 years old) were randomly assigned to 7-day treatment with Ginkgo (120 mg/day, n=15) or matched placebo (n=16). They were given a battery of cognitive tests and measurements of mood and menopausal symptoms at baseline (before treatment began) and at the end of 7 days. The group treated with Ginkgo was significantly better than the placebo group in a matching-to-sample test of nonverbal memory, but the groups did not differ in immediate or delayed paragraph recall or in delayed recall of pictures. In a test of frontal lobe function (rule shifting) and in the Paced Auditory Serial Addition Test (PASAT) (which measures sustained attention but also involves frontal lobe function), the group treated with Ginkgo performed significantly better than the placebo group. However, the groups did not differ in a test of planning. The treatments did not differ in their effects on the volunteers' ratings of menopausal symptoms, sleepiness, bodily symptoms or aggression. The benefits of Ginkgo on memory and frontal lobe function found in this study are modest but are unlikely to be secondary to major mood changes.