Sleep and exercise could be as powerful as any 'smart drug'

You don't have to take a pill to boost your brain power.

According to a 2015 meta-analysis by Oxford researchers, non-pharmacological forms of cognitive enhancement (NPCE) like sleep, exercise, and brain-training appear to do as much to improve cognition as pharmacological ones like modafinil, methylphenidate, and caffeine (also known as PCE).

"Although meta-analyses allowing a quantitative comparison of effectiveness across techniques are lacking to date, we can conclude that PCE is not more effective than NPCE," researchers Lucius Caviola and Nadira Faber write.

On one hand, smart drugs have been shown to increase attention, working memory, speed of processing, and wakefulness, among other positive effects. They typically work by influencing levels of neurotransmitters like serotonin, dopamine, and noradrenaline in your brain.

On the other hand:

- Good sleep habits seem to improve memory, creativity, and problem-solving speed. Even a six-minute nap has been shown to help.

- Acute exercise (i.e., brief bouts of high intensity training) has been linked to increased motivation and improvements to memory and speed of learning, with some effects lasting up to 48 hours later. Regular exercise has been linked to improvements in size, blood flow, and connectivity of important parts of the brain, as well as better memory, attention, executive functions, processing speed, and academic performance.

- Specifically designed computerized training programs have been shown to enhance memory, attention, visual processing speed, and executive function, with effects lasting as long as 3 months. It's generally assumed that other mental challenges, from playing Tetris to learning another language or trying something new, have similar effects.

All of these cognitive enhancers, Caviola and Faber conclude, have some moderately beneficial effects, which is to say they may help in some situations but won't turn you into Einstein. And again, the natural methods appear to work just as well as the pharmacological.

Smart drugs also come with downsides not found in natural drugs. Aside from various potential various potential health risks, they have been shown to impair cognition in some cases.

Modafinil, for instance, has also been linked to impaired creativity and flexible thinking and overconfidence in judgment. A recent study showed that chess players on smart drugs were worse at time management, for example. And it's not uncommon to hear about students taking methylphenidate (e.g., Ritalin) to help them study but getting distracted and spending hours focused on, say, reorganizing their closet.

This is, of course, not what you'll hear in some online forums devoted to the use of smart drugs. However, Caviola and Faber warn of a broad "overestimation of PCE effectiveness ... paired with an underestimation of potential side-effects."

It's worth noting too that we may be in early days for research and development of PCE, and it's possible that future studies or new pills will show stronger effects.

Still, Caviola and Faber note that the effects of cognitive enhancement of any kind seem to be limited, especially for people who are already cognitive high-performers (who might, for instance, already have optimal levels of neurotransmitters in their brain). In other words, sleep, exercise, and training may be all you ever need.