Cocoa flavanols (CF) positively influence physiological processes in ways which suggest that their consumption may improve aspects of cognitive function. This study investigated the acute cognitive and subjective effects of CF consumption during sustained mental demand. In this randomized, controlled, double-blinded, balanced, three period crossover trial 30 healthy adults consumed drinks containing 520 mg, 994 mg CF and a matched control, with a 3-day washout between drinks. Assessments included the state anxiety inventory and repeated 10-min cycles of a Cognitive Demand Battery comprising of two serial subtraction tasks (Serial Threes and Serial Sevens), a Rapid Visual Information Processing (RVIP) task and a mental fatigue scale, over the course of 1 h. Consumption of both 520 mg and 994 mg CF significantly improved Serial Threes performance. The 994 mg CF beverage significantly speeded RVIP responses but also resulted in more errors during Serial Sevens. Increases in self-reported mental fatigue were significantly attenuated by the consumption of the 520 mg CF beverage only. This is the first report of acute cognitive improvements following CF consumption in healthy adults. While the mechanisms underlying the effects are unknown they may be related to known effects of CF on endothelial function and blood flow.
Because modafinil works in a manner similar to methylphenidate, it also bears similar risks. The improper dosage or abuse of modafinil may lead to the disrupted development of executive controls like decision-making and working memory. Modafinil’s effects may also depend upon the IQ of the taker. Two university studies determined that in a test of sustained attention, modafinil only improved cognition in the group with “lower” IQs. Although safer than other stimulants due to its milder effect on neurotransmitter levels, there are still risks associated with any kind of drug that affects dopaminergic neurotransmission, mostly because this can lead to addiction and, similar to a pornography user who needs increasingly fringe porn to achieve the same effect, can produce a resistance or lowered sensitivity to dopamine.
The main concern with pharmaceutical drugs is adverse effects, which also apply to nootropics with undefined effects. Long-term safety evidence is typically unavailable for nootropics.[13] Racetams — piracetam and other compounds that are structurally related to piracetam — have few serious adverse effects and low toxicity, but there is little evidence that they enhance cognition in people having no cognitive impairments.[19]