Proof-of-Concept Randomized Controlled Study Of Cognition Effects Of The Proprietary Extract Sceletium Tortuosum (Zembrin) Targeting Phosphodiesterase-4 In Cognitively Healthy Subjects: Implications For Alzheimer's Dementia
|Trial Design||Double blind|
|Trial Length||2-4 Weeks|
|Number of Subjects||16|
25mg of a 2:1 extract of sceletium tortuosum (0.4% total alkaloids) in otherwise cognitively healthy middle-aged subjects (45-65yrs) daily for three weeks in this preliminary study found that supplementation found an increase in executive function and cognitive flexibility (assessed by the CNS Vital SignR test) compared to placebo.
Other parameters (complex attention, reaction time, psychomotor speed, procesisng speed, visual and verbal memory, composite memory, and neurocognitive index) did not differ significantly between groups.
While not statistically significant, there appeared to be an increase in mood with supplementation compared to placebo and there was a (barely; P = 0.049) significant improvement in subjective reports of sleep quality.