In one study, 41 women aged 64 to 79 with memory complaints took a daily multivitamin and herbal supplement or a placebo. The herbs were ginkgo biloba
and bacopa monnieri along with a standard multivitamin.
Before the study, and after 16 weeks, doctors measured brain electrical activity while showing the women visual images. While there were no changes for placebo, women in the multivitamin and herb combination group had favorable responses in brain electrical activity, boosting performance accuracy and enhancing neural efficiency. Doctors believe the herbs may increase the length and strength of brain nerve-signaling activity.