The Lamiaceae family of plants includes psychoactive herbs such as rosemary, lemon-balm, peppermint and sage, which have been shown to express high levels of phenolic acids and polyphenols.
Extracts from this family of plants often share common mechanisms of action relevant to the brain - such as inhibition of acetylcholinesterase and binding allosterically to gamma-Aminobutyric acid (GABAA), nicotinic and muscarinic receptors - attributable to their terpene content.
The phenolic constituents have also demonstrated cognitive effects such as increases in brain-derived neurotrophic factor (BDNF), and antioxidant and anti-inflammatory activities in neurons. A recent trial by Kennedy. D. O., et al demonstrated the more robust effects - acutely on energy and mood - which can be achieved when combining phenolics (coffee berry, apple catechins and blueberry anthocyanins) and terpenes (sage and ginseng) into a single supplement.
Human RCTs have demonstrated robust and consistent acute cognitive effects of Salvia lavandulaefolia (Spanish sage) essential oil.However the authors of the current study argue it has not been researched whether chronic effects could be elicited nor whether different effects are created when Salvia officinalis (common sage) polyphenols and Salvia lavandulaefolia (lavender leaved sage) terpenoids are co-administered.
The current study, funded by the makers of Cognivia supplement Nexira SAS, aimed to discover whether the Salvia and phenolic combination (Cognivia) can produce positive effects on memory in healthy adults (n=94, 69 female and 25 male, mean age 43.9 years) and how it might mediate persistent attentional and memory demands.
The researchers say the results demonstrate a cumulative benefit of the supplement on the accuracy and working memory performance cognitive domains. The report states: "The most convincing effects of sage were seen on day 29 and the existence of pure chronic effects on these measures suggests that these effects are the result of a cumulative effect."
Participants consumed either placebo or 600 mg Cognivia every day for one month. The selected dose contained 400 mg of aqueous extract from Salvia officinalis leaves (polyphenols) and 50 µL of Salvia lavandulaefolia essential oil (terpenoids).
In the first visit to the lab, participants completed a Caffeine Consumption Questionnaire and State-Trait Anxiety Inventory (STAI) trait subscale, and provided demographic data. For the following lab testing sessions (day 1 and day 29), participants attended after having consumed a standardised breakfast (they refrained from alcohol for 24 h and caffeine for 18 h prior).
They completed the STAI and a cognitive assessment (Computerised Mental Performance Assessment System, COMPASS), followed by measurements of blood pressure and heart rate.They then consumed their treatment. Two further cognitive assessments (plus blood pressure and heart rate) identical to the pre-dose assessment commenced at two hours and four hours post-dose.
The following measures were analysed: accuracy of attention, speed of attention, working memory, speed of memory and episodic memory.
The report states the results demonstrate clear, cumulative benefits of sage to individual task performance as well as a decrease in natural performance declines; with the effects isolated to the accuracy and working memory performance cognitive domains.
They note the most convincing effects of sage are seen on day 29 suggesting a cumulative effect.
The researchers note that 69% of participants in the intervention group were able to subjectively detect that they had been in the active intervention group. Some of this awareness was due the perception of a herbal taste during reflux which could theoretically have led to a placebo effect, but the report says some of the participants said they identified a change in mental ability, which would suggest an acute effect.
The researchers say future trials should focus on disentangling the working and spatial memory effects of this intervention in humans with an extended time frame of perhaps several months. Validating the CaMKII mechanism in humans would also be advantageous, they say.
Kennedy. D. O., et al
"The Acute and Chronic Cognitive Effects of a Sage Extract: A Randomized, Placebo Controlled Study in Healthy Humans"