Eighty-four healthy volunteers who were not taking any medication or other herbal preparation, and reported no head injuries, commenced the study. Eight participants withdrew after the first testing session, four from each group. Only one of these was due to an adverse (gastrointestinal) reaction to the Brahmi capsules. Two of the participants in the placebo group withdrew when they developed a medical condition. At the second testing session and a mid-trial telephone, call participants were asked about their memory function and given an opportunity to make other comments. On these occasions, no other participants reported adverse reactions. Seventy-six participants (28 males and 48 females) between the ages of 40 and 65 years (mean 49, S.D. 7), completed the study.

Design

The study utilized a double-blind, randomized placebo-controlled independent group design with two groups; a Bacopa monniera (Keenmind extract) group (n = 37) and a placebo group (n = 39).

Procedure

Participants were tested on three separate occasions for approximately one hour. In the first session pre-trial testing was completed (baseline) and the participants were given three months supply of capsules at the dosage recommended by the manufacturers (300 mg for persons under 90 kg, and 450 mg for persons over 90 kg, equivalent to 6g and 9g dried rhizome, respectively). Participants were contacted by telephone approximately six to eight weeks into the trial period to encourage compliance. A second testing session was conducted approximately three months later (3-month test), at which participants were instructed not to take any remaining capsules. A post-trial testing session occurred approximately six weeks after the end of the trial session.