2012-pase.pdf: “The Cognitive–Enhancing Effects of Bacopa monnieri: A Systematic Review of Randomized, Controlled Human Clinical Trials”, (2012-07-25; ):
Objectives: Traditional knowledge suggests that Bacopa monnieri enhances cognitive performance. Such traditional beliefs have now been scientifically tested through a handful of randomized, controlled human clinical trials. The current systematic review aimed to examine the scientific evidence as to whether Bacopa can enhance cognitive performance in humans.
Design: A systematic review of randomized controlled trials is presented. Multiple databases were systematically searched by multiple authors. Relevant trials were objectively assessed for methodological quality.
Subjects: The subjects studied were adult humans without dementia or cognitive impairment.
Intervention: Bacopa monnieri, including Bacopa extracts, were administered over long-term supplementation periods.
Outcome measures: Any validated cognitive test, whether a primary or secondary outcome.
Results: 6 studies met the final inclusion criteria and were included in review. Trials were all conducted over 12 weeks. Across trials, 3 different Bacopa extracts were used at dosages of 300–450 mg extract per day. All reviewed trials examined the effects of Bacopa on memory, while other cognitive domains were less well studied. There were no cognitive tests in the areas of auditory perceptual abilities or idea production and only a paucity of research in the domains of reasoning, number facility, and language behavior. Across studies, Bacopa improved performance on 9 of 17 tests in the domain of memory free recall. There was little evidence of enhancement in any other cognitive domains.
Conclusions: There is some evidence to suggest that Bacopa improves memory free recall with evidence for enhancement in other cognitive abilities currently lacking perhaps due to inconsistent measures employed by studies across these cognitive domains. Research into the nootropic effects of Bacopa is in its infancy, with research still yet to investigate the effects of Bacopa across all human cognitive abilities. Similarly, future research should examine the effects of Bacopa at varied dosages and across different extracts.
2013-kongkeaw.pdf: “Meta-analysis of , Chuenjid Kongkeaw, Piyameth Dilokthornsakul, Phurit Thanarangsarit, Nanteetip Limpeanchob, C. Norman Scholfield on cognitive effects of Bacopa monnieri extract”
Background: Brahmi (Bacopa monniera) is a traditional Indian medicinal plant which causes multiple effects on the central nervous system. The standardized extract of this plant has shown enhanced behavioural learning in preclinical studies and enhanced information processing in healthy volunteers.
Aim: To study the efficacy of standardized Bacopa monniera extract (SBME) in subjects with age-associated memory impairment (AAMI) without any evidence of dementia or psychiatric disorder.
Methods: A double-blind, placebo-controlled randomized study design was employed. The subjects received either 125 mg of SBME or placebo twice a day for a period of 12 weeks followed by a placebo period of another 4 weeks (total duration of the trial 16 weeks). Each subject was evaluated for cognition on a battery of tests comprising mental control, logical memory, digit forward, digit backward, visual reproduction and paired associate learning.
Results: SBME produced significant improvement on mental control, logical memory and paired associated learning during the 12-week drug therapy.
Conclusion: SBME is efficacious in subjects with age-associated memory impairment.
Objectives: Study aims were to evaluate effects of Bacopa monnieri whole plant standardized dry extract on cognitive function and affect and its safety and tolerability in healthy elderly study participants.
Design: The study was a randomized, double-blind, placebo-with a placebo run-in of 6 weeks and a treatment period of 12 weeks.
Setting/Location: Volunteers were recruited from the community to a clinic in Portland, Oregon by public notification.
Subjects: Fifty-four (54) participants, 65 or older (mean 73.5 years), without clinical signs of dementia, were recruited and randomized to Bacopa or placebo. Forty-eight (48) completed the study with 24 in each group.
Interventions: Standardized B. monnieri extract 300 mg/day or a similar placebo tablet orally for 12 weeks.
Outcome Measures: The primary outcome variable was the delayed recall score from the Rey Auditory Verbal Learning Test (AVLT). Other cognitive measures were the Stroop Task assessing the ability to ignore irrelevant information, the Divided Attention Task (DAT), and the Wechsler Adult Intelligence Scale (WAIS) letter-digit test of immediate working memory. Affective measures were the State-Trait Anxiety Inventory, Center for Epidemiologic Studies Depression scale (CESD)-10 depression scale, and the Profile of Mood States. Vital signs were also monitored.
Results: Controlling for baseline cognitive deficit using the Blessed Orientation-Memory-Concentration test, Bacopa participants had enhanced AVLT delayed word recall memory scores relative to placebo. Stroop results were similarly significant, with the Bacopa group improving and the placebo group unchanged. CESD-10 depression scores, combined state plus trait anxiety scores, and heart rate decreased over time for the Bacopa group but increased for the placebo group. No effects were found on the DAT, WAIS digit task, mood, or blood pressure. The dose was well tolerated with few adverse events (Bacopa n = 9, placebo n = 10), primarily stomach upset.
Conclusions: This study provides further evidence that B. monnieri has potential for safely enhancing cognitive performance in the aging.
2008-stough.pdf: “Examining the , Zhou Hongyan effects of a special extract of Bacopa monniera on human cognitive functioning: 90 day double-blind placebo-controlled randomized trial”