The idea of humans using only 10% of their brain is a common “neuromyth” previously debunked in one of our articles. Possibly due to this misconception “smart drugs”, known as Cognitive Enhancers (CE) or nootropics are becoming more popular, especially among students [1]. Across several studies, the usage of CEs among students in different countries is reported to be up to 33%, depending on the definition of cognitive pharmaceutical doping [2]. The Global Drug survey indicated that, in 47.8% of the cases, students obtain nootropics from friends and family [3]. This raises the possibility of non-medical use of cognitive enhancers being a major public health concern, with the American Medical Association already speaking out against the off-label use of these compounds in 2016 [4]. Indeed, rather than “unlocking untapped potential”, most medical advice for improving brain function aspires to prevent a decline in cognitive-impaired individuals, e.g. in Alzheimer’s Disease or in patients with developing brain damage [1]. Due to their growing popularity, this article aims to provide a simplified overview of how CEs can affect cognition and summarize the current scientific consensus on whether nootropics work on healthy individuals.

Cognitive enhancers, are more commonly known as “study drugs”, “memory pills”, or “focus/concentration pills” and are known for their alleged ability to improve cognitive abilities. The brain can be simplistically described as a network of neurons talking to each other; such neuronal networks constitute the foundation for most brain functions including cognitive abilities [5]. Nootropics aim to improve cognition by modulating factors that affect either the communication among the neurons or neuronal health. In the first case, CEs can directly tweak the activity of neurotransmitters, the signals neurons use to communicate. In the latter, the promotion of better neuronal health can be achieved by protecting them from naturally harmful biological processes. An anti-oxidative (anti-oxidant) function of some nootropics can reduce the byproducts of cellular respiration. Others can increase nutrient availability and delivery, via increased blood circulation [6,7]. In a nutshell, by targeting and promoting neuronal health and communication, nootropics may potentially lead to the enhancement of cognitive abilities, including memory, attention and learning ability.

Furthermore, cognitive enhancers are not only subdivided by their mode of action but also by their origin. Hence, they can fall into either synthetic or natural subgroups. Synthetic molecules (as we previously defined here) are artificially produced through combinations of chemical substances. The most commonly prescribed and abused group of synthetic cognitive enhancers are central nervous system modulators (CNS modulator). They include amphetamine-type stimulants and other direct modulators of neurotransmitters, such as the household names Ritalin or Adderall. These drugs act to tweak the communication system of our neurons, leading to improved performance in attention and memory. Other CNS modulators include piracetam, modafinil and donepezil, which also exhibit potential benefits of improved aspects of cognitive abilities, albeit via influencing different signalling or “communication” pathways. Importantly, many CNS modulators influence other bodily functions, such as alertness, blood pressure and breathing rate. Thus, these modulators are usually only available on prescription due to their potency and dangerous side effects including potential addiction and mood/behavioural disorders [7].

On the other hand, natural cognitive enhancers usually come in the form of plant/herbal extracts. Certain natural plants such as Bacopa monnieri, Ginkgo biloba and Panax ginseng are believed to have nootropic outcomes regarding improved memory and learning capabilities [5–7]. More specifically, compounds found in these plants, e.g. bacosides and ginkgolides generally function by promoting neuronal health as anti-oxidants or through stimulatory properties. In addition, ginsenosides can also affect neurotransmitter release in the brain, possibly leading to better memory [6]. While the contents and effects of synthetic cognitive enhancers are known from extensive lab testing, natural ones often have complex chemical compositions that can differ based on many different factors [8]. Thus, the mechanisms of action of synthetic CEs are generally better described compared to natural ones.

In short, we discussed different biological approaches through which nootropics can influence brain behaviour. Most of the benefits conferred by nootropics have been confirmed in patients with diagnosed cognitive impairment, while their effects on healthy individuals remain unclear [6–8]. In the future, a controlled systemic review of a large pool of individuals is needed to determine any possible benefits along with all detrimental effects of short and long-term use of nootropics.