Table 4 lists the results of 27 tasks from 23 articles on the effects of d-AMP or MPH on working memory. The oldest and most commonly used type of working memory task in this literature is the Sternberg short-term memory scanning paradigm (Sternberg, 1966), in which subjects hold a set of items (typically letters or numbers) in working memory and are then presented with probe items, to which they must respond “yes” (in the set) or “no” (not in the set). The size of the set, and hence the working memory demand, is sometimes varied, and the set itself may be varied from trial to trial to maximize working memory demands or may remain fixed over a block of trials. Taken together, the studies that have used a version of this task to test the effects of MPH and d-AMP on working memory have found mixed and somewhat ambiguous results. No pattern is apparent concerning the specific version of the task or the specific drug. Four studies found no effect (Callaway, 1983; Kennedy, Odenheimer, Baltzley, Dunlap, & Wood, 1990; Mintzer & Griffiths, 2007; Tipper et al., 2005), three found faster responses with the drugs (Fitzpatrick, Klorman, Brumaghim, & Keefover, 1988; Ward et al., 1997; D. E. Wilson et al., 1971), and one found higher accuracy in some testing sessions at some dosages, but no main effect of drug (Makris et al., 2007). The meaningfulness of the increased speed of responding is uncertain, given that it could reflect speeding of general response processes rather than working memory–related processes. Aspects of the results of two studies suggest that the effects are likely due to processes other than working memory: D. E. Wilson et al. (1971) reported comparable speeding in a simple task without working memory demands, and Tipper et al. (2005) reported comparable speeding across set sizes.

Finally, a workforce high on stimulants wouldn’t necessarily be more productive overall. “One thinks ‘are these things dangerous?’ – and that’s important to consider in the short term,” says Huberman. “But there’s also a different question, which is: ‘How do you feel the day afterwards?’ Maybe you’re hyper-focused for four hours, 12 hours, but then you’re below baseline for 24 or 48.”

Some nootropics are more commonly used than others. These include nutrients like Alpha GPC, huperzine A, L-Theanine, bacopa monnieri, and vinpocetine. Other types of nootropics ware still gaining traction. With all that in mind, to claim there is a “best” nootropic for everyone would be the wrong approach since every person is unique and looking for different benefits.
If you’re suffering from blurred or distorted vision or you’ve noticed a sudden and unexplained decline in the clarity of your vision, do not try to self-medicate. It is one thing to promote better eyesight from an existing and long-held baseline, but if you are noticing problems with your eyes, then you should see an optician and a doctor to rule out underlying medical conditions.
Chocolate or cocoa powder (, contains the stimulants caffeine and the caffeine metabolite theobromine, so it’s not necessarily surprising if cocoa powder was a weak stimulant. It’s also a witch’s brew of chemicals such as polyphenols and flavonoids some of which have been fingered as helpful10, which all adds up to an unclear impact on health (once you control for eating a lot of sugar).
The main area of the brain effected by smart pills is the prefrontal cortex, where representations of our goals for the future are created. Namely, the prefrontal cortex consists of pyramidal cells that keep each other firing. However in some instances they can become disconnected due to chemical imbalances, or due to being tired, stressed, and overworked.
Nootropics – sometimes called smart drugs – are compounds that enhance brain function. They’re becoming a popular way to give your mind an extra boost. According to one Telegraph report, up to 25% of students at leading UK universities have taken the prescription smart drug modafinil [1], and California tech startup employees are trying everything from Adderall to LSD to push their brains into a higher gear [2].
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]