The miniaturization of electronic components has been crucial to smart pill design. As cloud computing and wireless communication platforms are integrated into the health care system, the use of smart pills for monitoring vital signs and medication compliance is likely to increase. In the long term, smart pills are expected to be an integral component of remote patient monitoring and telemedicine. As the call for noninvasive point-of-care testing increases, smart pills will become mainstream devices.
After my rudimentary stacking efforts flamed out in unspectacular fashion, I tried a few ready-made stacks—brand-name nootropic cocktails that offer to eliminate the guesswork for newbies. They were just as useful. And a lot more expensive. Goop’s Braindust turned water into tea-flavored chalk. But it did make my face feel hot for 45 minutes. Then there were the two pills of Brain Force Plus, a supplement hawked relentlessly by Alex Jones of InfoWars infamy. The only result of those was the lingering guilt of knowing that I had willingly put $19.95 in the jorts pocket of a dipshit conspiracy theorist.
In this large population-based cohort, we saw consistent robust associations between cola consumption and low BMD in women. The consistency of pattern across cola types and after adjustment for potential confounding variables, including calcium intake, supports the likelihood that this is not due to displacement of milk or other healthy beverages in the diet. The major differences between cola and other carbonated beverages are caffeine, phosphoric acid, and cola extract. Although caffeine likely contributes to lower BMD, the result also observed for decaffeinated cola, the lack of difference in total caffeine intake across cola intake groups, and the lack of attenuation after adjustment for caffeine content suggest that caffeine does not explain these results. A deleterious effect of phosphoric acid has been proposed (26). Cola beverages contain phosphoric acid, whereas other carbonated soft drinks (with some exceptions) do not.
This formula presents a relatively high price and one bottle of 60 tables, at the recommended dosage of two tablets per day with a meal, a bottle provides a month’s supply. The secure online purchase is available on the manufacturer’s site as well as at several online retailers. Although no free trials or money back guarantees are available at this time, the manufacturer provides free shipping if the desired order exceeds a certain amount. With time different online retailers could offer some advantages depending on the amount purchased, so an online research is advised before purchase, as to assess the market and find the best solution.
Adderall is an amphetamine, used as a drug to help focus and concentration in people with ADHD, and promote wakefulness for sufferers of narcolepsy. Adderall increases levels of dopamine and norepinephrine in the brain, along with a few other chemicals and neurotransmitters. It’s used off-label as a study drug, because, as mentioned, it is believed to increase focus and concentration, improve cognition and help users stay awake. Please note: Side Effects Possible.
On the other metric, suppose we removed the creatine? Dropping 4 grams of material means we only need to consume 5.75 grams a day, covered by 8 pills (compared to 13 pills). We save 5,000 pills, which would have cost $45 and also don’t spend the $68 for the creatine; assuming a modafinil formulation, that drops our $1761 down to $1648 or $1.65 a day. Or we could remove both the creatine and modafinil, for a grand total of $848 or $0.85 a day, which is pretty reasonable.
As mentioned earlier, cognitive control is needed not only for inhibiting actions, but also for shifting from one kind of action or mental set to another. The WCST taxes cognitive control by requiring the subject to shift from sorting cards by one dimension (e.g., shape) to another (e.g., color); failures of cognitive control in this task are manifest as perseverative errors in which subjects continue sorting by the previously successful dimension. Three studies included the WCST in their investigations of the effects of d-AMP on cognition (Fleming et al., 1995; Mattay et al., 1996, 2003), and none revealed overall effects of facilitation. However, Mattay et al. (2003) subdivided their subjects according to COMT genotype and found differences in both placebo performance and effects of the drug. Subjects who were homozygous for the val allele (associated with lower prefrontal dopamine activity) made more perseverative errors on placebo than other subjects and improved significantly with d-AMP. Subjects who were homozygous for the met allele performed best on placebo and made more errors on d-AMP.

Government restrictions and difficulty getting approval for various medical devices is expected to impede market growth. The stringency of approval by regulatory authorities is accompanied by the high cost of smart pills to challenge the growth of the smart pills market. However, the demand for speedy diagnosis, and improving reimbursement policies are likely to reveal market opportunities.

Flaxseed oil is, ounce for ounce, about as expensive as fish oil, and also must be refrigerated and goes bad within months anyway. Flax seeds on the other hand, do not go bad within months, and cost dollars per pound. Various resources I found online estimated that the ALA component of human-edible flaxseed to be around 20% So Amazon’s 6lbs for $14 is ~1.2lbs of ALA, compared to 16fl-oz of fish oil weighing ~1lb and costing ~$17, while also keeping better and being a calorically useful part of my diet. The flaxseeds can be ground in an ordinary food processor or coffee grinder. It’s not a hugely impressive cost-savings, but I think it’s worth trying when I run out of fish oil.
Cognition is a suite of mental phenomena that includes memory, attention and executive functions, and any drug would have to enhance executive functions to be considered truly ‘smart’. Executive functions occupy the higher levels of thought: reasoning, planning, directing attention to information that is relevant (and away from stimuli that aren’t), and thinking about what to do rather than acting on impulse or instinct. You activate executive functions when you tell yourself to count to 10 instead of saying something you may regret. They are what we use to make our actions moral and what we think of when we think about what makes us human.

One thing to notice is that the default case matters a lot. This asymmetry is because you switch decisions in different possible worlds - when you would take Adderall but stop you’re in the world where Adderall doesn’t work, and when you wouldn’t take Adderall but do you’re in the world where Adderall does work (in the perfect information case, at least). One of the ways you can visualize this is that you don’t penalize tests for giving you true negative information, and you reward them for giving you true positive information. (This might be worth a post by itself, and is very Litany of Gendlin.)


After I ran out of creatine, I noticed the increased difficulty, and resolved to buy it again at some point; many months later, there was a Smart Powders sale so bought it in my batch order, $12 for 1000g. As before, it made Taekwondo classes a bit easier. I paid closer attention this second time around and noticed that as one would expect, it only helped with muscular fatigue and did nothing for my aerobic issues. (I hate aerobic exercise, so it’s always been a weak point.) I eventually capped it as part of a sulbutiamine-DMAE-creatine-theanine mix. This ran out 1 May 2013. In March 2014, I spent $19 for 1kg of micronized creatine monohydrate to resume creatine use and also to use it as a placebo in a honey-sleep experiment testing Seth Roberts’s claim that a few grams of honey before bedtime would improve sleep quality: my usual flour placebo being unusable because the mechanism might be through simple sugars, which flour would digest into. (I did not do the experiment: it was going to be a fair amount of messy work capping the honey and creatine, and I didn’t believe Roberts’s claims for a second - my only reason to do it would be to prove the claim wrong but he’d just ignore me and no one else cares.) I didn’t try measuring out exact doses but just put a spoonful in my tea each morning (creatine is tasteless). The 1kg lasted from 25 March to 18 September or 178 days, so ~5.6g & $0.11 per day.
Null results are generally less likely to be published. Consistent with the operation of such a bias in the present literature, the null results found in our survey were invariably included in articles reporting the results of multiple tasks or multiple measures of a single task; published single-task studies with exclusively behavioral measures all found enhancement. This suggests that some single-task studies with null results have gone unreported. The present mixed results are consistent with those of other recent reviews that included data from normal subjects, using more limited sets of tasks or medications (Advokat, 2010; Chamberlain et al., 2010; Repantis, Schlattmann, Laisney, & Heuser, 2010).
Some data suggest that cognitive enhancers do improve some types of learning and memory, but many other data say these substances have no effect. The strongest evidence for these substances is for the improvement of cognitive function in people with brain injury or disease (for example, Alzheimer's disease and traumatic brain injury). Although "popular" books and companies that sell smart drugs will try to convince you that these drugs work, the evidence for any significant effects of these substances in normal people is weak. There are also important side-effects that must be considered. Many of these substances affect neurotransmitter systems in the central nervous system. The effects of these chemicals on neurological function and behavior is unknown. Moreover, the long-term safety of these substances has not been adequately tested. Also, some substances will interact with other substances. A substance such as the herb ma-huang may be dangerous if a person stops taking it suddenly; it can also cause heart attacks, stroke, and sudden death. Finally, it is important to remember that products labeled as "natural" do not make them "safe."
The next morning, four giant pills’ worth of the popular piracetam-and-choline stack made me... a smidge more alert, maybe? (Or maybe that was just the fact that I had slept pretty well the night before. It was hard to tell.) Modafinil, which many militaries use as their “fatigue management” pill of choice, boasts glowing reviews from satisfied users. But in the United States, civilians need a prescription to get it; without one, they are stuck using adrafinil, a precursor substance that the body metabolizes into modafinil after ingestion. Taking adrafinil in lieu of coffee just made me keenly aware that I hadn’t had coffee.
Lebowitz says that if you're purchasing supplements to improve your brain power, you're probably wasting your money. "There is nothing you can buy at your local health food store that will improve your thinking skills," Lebowitz says. So that turmeric latte you've been drinking everyday has no additional brain benefits compared to a regular cup of java.

That said, there are plenty of studies out there that point to its benefits. One study, published in the British Journal of Pharmacology, suggests brain function in elderly patients can be greatly improved after regular dosing with Piracetam. Another study, published in the journal Psychopharmacology, found that Piracetam improved memory in most adult volunteers. And another, published in the Journal of Clinical Psychopharmacology, suggests it can help students, especially dyslexic students, improve their nonverbal learning skills, like reading ability and reading comprehension. Basically, researchers know it has an effect, but they don’t know what or how, and pinning it down requires additional research.


Two increasingly popular options are amphetamines and methylphenidate, which are prescription drugs sold under the brand names Adderall and Ritalin. In the United States, both are approved as treatments for people with ADHD, a behavioural disorder which makes it hard to sit still or concentrate. Now they’re also widely abused by people in highly competitive environments, looking for a way to remain focused on specific tasks.


Rogers RD, Blackshaw AJ, Middleton HC, Matthews K, Hawtin K, Crowley C, Robbins TW. Tryptophan depletion impairs stimulus-reward learning while methylphenidate disrupts attentional control in healthy young adults: Implications for the monoaminergic basis of impulsive behaviour. Psychopharmacology. 1999;146:482–491. doi: 10.1007/PL00005494. [PubMed] [CrossRef]
Table 3 lists the results of 24 tasks from 22 articles on the effects of d-AMP or MPH on learning, assessed by a variety of declarative and nondeclarative memory tasks. Results for the 24 tasks are evenly split between enhanced learning and null results, but they yield a clearer pattern when the nature of the learning task and the retention interval are taken into account. In general, with single exposures of verbal material, no benefits are seen immediately following learning, but later recall and recognition are enhanced. Of the six articles reporting on memory performance (Camp-Bruno & Herting, 1994; Fleming, Bigelow, Weinberger, & Goldberg, 1995; Rapoport, Busbaum, & Weingartner, 1980; Soetens, D’Hooge, & Hueting, 1993; Unrug, Coenen, & van Luijtelaar, 1997; Zeeuws & Soetens 2007), encompassing eight separate experiments, only one of the experiments yielded significant memory enhancement at short delays (Rapoport et al., 1980). In contrast, retention was reliably enhanced by d-AMP when subjects were tested after longer delays, with recall improved after 1 hr through 1 week (Soetens, Casaer, D’Hooge, & Hueting, 1995; Soetens et al., 1993; Zeeuws & Soetens, 2007). Recognition improved after 1 week in one study (Soetens et al., 1995), while another found recognition improved after 2 hr (Mintzer & Griffiths, 2007). The one long-term memory study to examine the effects of MPH found a borderline-significant reduction in errors when subjects answered questions about a story (accompanied by slides) presented 1 week before (Brignell, Rosenthal, & Curran, 2007).
** = Important note - whilst BrainZyme is scientifically proven to support concentration and mental performance, it is not a replacement for a good diet, moderate exercise or sleep. BrainZyme is also not a drug, medicine or pharmaceutical. It is a natural-sourced, vegan food supplement with ingredients that are scientifically proven to support cognition, concentration, mental performance and reduction of tiredness. You should always consult with your Doctor if you require medical attention.
Ngo has experimented with piracetam himself (“The first time I tried it, I thought, ‘Wow, this is pretty strong for a supplement.’ I had a little bit of reflux, heartburn, but in general it was a cognitive enhancer. . . . I found it helpful”) and the neurotransmitter DMEA (“You have an idea, it helps you finish the thought. It’s for when people have difficulty finishing that last connection in the brain”).

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In my last post, I talked about the idea that there is a resource that is necessary for self-control…I want to talk a little bit about the candidate for this resource, glucose. Could willpower fail because the brain is low on sugar? Let’s look at the numbers. A well-known statistic is that the brain, while only 2% of body weight, consumes 20% of the body’s energy. That sounds like the brain consumes a lot of calories, but if we assume a 2,400 calorie/day diet - only to make the division really easy - that’s 100 calories per hour on average, 20 of which, then, are being used by the brain. Every three minutes, then, the brain - which includes memory systems, the visual system, working memory, then emotion systems, and so on - consumes one (1) calorie. One. Yes, the brain is a greedy organ, but it’s important to keep its greediness in perspective… Suppose, for instance, that a brain in a person exerting their willpower - resisting eating brownies or what have you - used twice as many calories as a person not exerting willpower. That person would need an extra one third of a calorie per minute to make up the difference compared to someone not exerting willpower. Does exerting self control burn more calories?
The advantage of adrafinil is that it is legal & over-the-counter in the USA, so one removes the small legal risk of ordering & possessing modafinil without a prescription, and the retailers may be more reliable because they are not operating in a niche of dubious legality. Based on comments from others, the liver problem may have been overblown, and modafinil vendors post-2012 seem to have become more unstable, so I may give adrafinil (from another source than Antiaging Central) a shot when my modafinil/armodafinil run out.
I bought 500g of piracetam (Examine.com; FDA adverse events) from Smart Powders (piracetam is one of the cheapest nootropics and SP was one of the cheapest suppliers; the others were much more expensive as of October 2010), and I’ve tried it out for several days (started on 7 September 2009, and used it steadily up to mid-December). I’ve varied my dose from 3 grams to 12 grams (at least, I think the little scoop measures in grams), taking them in my tea or bitter fruit juice. Cranberry worked the best, although orange juice masks the taste pretty well; I also accidentally learned that piracetam stings horribly when I got some on a cat scratch. 3 grams (alone) didn’t seem to do much of anything while 12 grams gave me a nasty headache. I also ate 2 or 3 eggs a day.
With subtle effects, we need a lot of data, so we want at least half a year (6 blocks) or better yet, a year (12 blocks); this requires 180 actives and 180 placebos. This is easily covered by $11 for Doctor’s Best Best Lithium Orotate (5mg), 200-Count (more precisely, Lithium 5mg (from 125mg of lithium orotate)) and $14 for 1000x1g empty capsules (purchased February 2012). For convenience I settled on 168 lithium & 168 placebos (7 pill-machine batches, 14 batches total); I can use them in 24 paired blocks of 7-days/1-week each (48 total blocks/48 weeks). The lithium expiration date is October 2014, so that is not a problem
Though coffee gives instant alertness, the effect lasts only for a short while. People who drink coffee every day may develop caffeine tolerance; this is the reason why it is still important to control your daily intake. It is advisable that an individual should not consume more than 300 mg of coffee a day. Caffeine, the world’s favorite nootropic has fewer side effects, but if consumed abnormally in excess, it can result in nausea, restlessness, nervousness, and hyperactivity. This is the reason why people who need increased sharpness would instead induce L-theanine, or some other Nootropic, along with caffeine. Today, you can find various smart drugs that contain caffeine in them. OptiMind, one of the best and most sought-after nootropics in the U.S, containing caffeine, is considered best brain supplement for adults and kids when compared to other focus drugs present in the market today.

An entirely different set of questions concerns cognitive enhancement in younger students, including elementary school and even preschool children. Some children can function adequately in school without stimulants but perform better with them; medicating such children could be considered a form of cognitive enhancement. How often does this occur? What are the roles and motives of parents, teachers, and pediatricians in these cases? These questions have been discussed elsewhere and deserve continued attention (Diller, 1996; Singh & Keller, 2010).
Coconut oil was recommended by Pontus Granström on the Dual N-Back mailing list for boosting energy & mental clarity. It is fairly cheap (~$13 for 30 ounces) and tastes surprisingly good; it has a very bad reputation in some parts, but seems to be in the middle of a rehabilitation. Seth Robert’s Buttermind experiment found no mental benefits to coconut oil (and benefits to eating butter), but I wonder.

Several new medications are on the market and in development for Alzheimer's disease, a progressive neurological disease leading to memory loss, language deterioration, and confusion that afflicts about 4.5 million Americans and is expected to strike millions more as the baby boom generation ages. Yet the burning question for those who aren't staring directly into the face of Alzheimer's is whether these medications might make us smarter.
SOURCES: Marvin Hausman, MD, CEO, Axonyx Inc. Axel Unterbeck, PhD, president, chief scientific officer, Memory Pharmaceuticals. Martha Farah, PhD, professor, department of psychiatry, University of Pennsylvania. Howard Gardner, PhD, Hobbs Professor of Education and Cognition, Harvard Graduate School of Education. Nature Reviews Neuroscience, May 2004. Neurology, July 2002. Alzheimer's Association.
In our list of synthetic smart drugs, Noopept may be the genius pill to rule them all. Up to 1000 times stronger than Piracetam, Noopept may not be suitable for everyone. This nootropic substance requires much smaller doses for enhanced cognitive function. There are plenty of synthetic alternatives to Adderall and prescription ADHD medications. Noopept may be worth a look if you want something powerful over the counter.
2ml is supposed to translate to 24mg, which is a big dose. I do not believe any of the commercial patches go much past that. I asked Wedrifid, whose notes inspired my initial interest, and he was taking perhaps 2-4mg, and expressed astonishment that I might be taking 24mg. (2mg is in line with what I am told by another person - that 2mg was so much that they actually felt a little sick. On the other hand, in one study, the subjects could not reliably distinguish between 1mg and placebo24.) 24mg is particularly troubling in that I weigh ~68kg, and nicotine poisoning and the nicotine LD50 start, for me, at around 68mg of nicotine. (I reflected that the entire jar could be a useful murder weapon, although nicotine presumably would be caught in an autopsy’s toxicology screen; I later learned nicotine was an infamous weapon in the 1800s before any test was developed. It doesn’t seem used anymore, but there are still fatal accidents due to dissolved nicotine.) The upper end of the range, 10mg/kg or 680mg for me, is calculated based on experienced smokers. Something is wrong here - I can’t see why I would have nicotine tolerance comparable to a hardened smoker, inasmuch as my maximum prior exposure was second-hand smoke once in a blue moon. More likely is that either the syringe is misleading me or the seller NicVape sold me something more dilute than 12mg/ml. (I am sure that it’s not simply plain water; when I mix the drops with regular water, I can feel the propylene glycol burning as it goes down.) I would rather not accuse an established and apparently well-liked supplier of fraud, nor would I like to simply shrug and say I have a mysterious tolerance and must experiment with doses closer to the LD50, so the most likely problem is a problem with the syringe. The next day I altered the procedure to sucking up 8ml, squirting out enough fluid to move the meniscus down to 7ml, and then ejecting the rest back into the container. The result was another mild clean stimulation comparable to the previous 1ml days. The next step is to try a completely different measuring device, which doesn’t change either.
Looking at the prices, the overwhelming expense is for modafinil. It’s a powerful stimulant - possibly the single most effective ingredient in the list - but dang expensive. Worse, there’s anecdotal evidence that one can develop tolerance to modafinil, so we might be wasting a great deal of money on it. (And for me, modafinil isn’t even very useful in the daytime: I can’t even notice it.) If we drop it, the cost drops by a full $800 from $1761 to $961 (almost halving) and to $0.96 per day. A remarkable difference, and if one were genetically insensitive to modafinil, one would definitely want to remove it.
My intent here is not to promote illegal drugs or promote the abuse of prescription drugs. In fact, I have identified which drugs require a prescription. If you are a servicemember and you take a drug (such as Modafinil and Adderall) without a prescription, then you will fail a urinalysis test. Thus, you will most likely be discharged from the military.
Remember: The strictest definition of nootropics today says that for a substance to be a true brain-boosting nootropic it must have low toxicity and few side effects. Therefore, by definition, a nootropic is safe to use. However, when people start stacking nootropics indiscriminately, taking megadoses, or importing them from unknown suppliers that may have poor quality control, it’s easy for safety concerns to start creeping in.
Not all drug users are searching for a chemical escape hatch. A newer and increasingly normalized drug culture is all about heightening one’s current relationship to reality—whether at work or school—by boosting the brain’s ability to think under stress, stay alert and productive for long hours, and keep track of large amounts of information. In the name of becoming sharper traders, medical interns, or coders, people are taking pills typically prescribed for conditions including ADHD, narcolepsy, and Alzheimer’s. Others down “stacks” of special “nootropic” supplements.
Nootropics are a great way to boost your productivity. Nootropics have been around for more than 40 years and today they are entering the mainstream. If you want to become the best you, nootropics are a way to level up your life. Nootropics are always personal and what works for others might not work for you. But no matter the individual outcomes, nootropics are here to make an impact!
The magnesium was neither randomized nor blinded and included mostly as a covariate to avoid confounding (the Noopept coefficient & t-value increase somewhat without the Magtein variable), so an OR of 1.9 is likely too high; in any case, this experiment was too small to reliably detect any effect (~26% power, see bootstrap power simulation in the magnesium section) so we can’t say too much.
…Four subjects correctly stated when they received nicotine, five subjects were unsure, and the remaining two stated incorrectly which treatment they received on each occasion of testing. These numbers are sufficiently close to chance expectation that even the four subjects whose statements corresponded to the treatments received may have been guessing.
Another important epidemiological question about the use of prescription stimulants for cognitive enhancement concerns the risk of dependence. MPH and d-AMP both have high potential for abuse and addiction related to their effects on brain systems involved in motivation. On the basis of their reanalysis of NSDUH data sets from 2000 to 2002, Kroutil and colleagues (2006) estimated that almost one in 20 nonmedical users of prescription ADHD medications meets criteria for dependence or abuse. This sobering estimate is based on a survey of all nonmedical users. The immediate and long-term risks to individuals seeking cognitive enhancement remain unknown.
As it happened, Health Supplement Wholesalers (since renamed Powder City) offered me a sample of their products, including their 5g Noopept powder ($13). I’d never used HSW before & they had some issues in the past; but I haven’t seen any recent complaints, so I was willing to try them. My 5g from batch #130830 arrived quickly (photos: packaging, powder contents). I tried some (tastes just slightly unpleasant, like an ultra-weak piracetam), and I set about capping the fluffy white flour-like powder with the hilariously tiny scoop they provide.
Another interpretation of the mixed results in the literature is that, in some cases at least, individual differences in response to stimulants have led to null results when some participants in the sample are in fact enhanced and others are not. This possibility is not inconsistent with the previously mentioned ones; both could be at work. Evidence has already been reviewed that ability level, personality, and COMT genotype modulate the effect of stimulants, although most studies in the literature have not broken their samples down along these dimensions. There may well be other as-yet-unexamined individual characteristics that determine drug response. The equivocal nature of the current literature may reflect a mixture of substantial cognitive-enhancement effects for some individuals, diluted by null effects or even counteracted by impairment in others.
Many over the counter and prescription smart drugs fall under the category of stimulants. These substances contribute to an overall feeling of enhanced alertness and attention, which can improve concentration, focus, and learning. While these substances are often considered safe in moderation, taking too much can cause side effects such as decreased cognition, irregular heartbeat, and cardiovascular problems.
Hericium erinaceus (Examine.com) was recommended strongly by several on the ImmInst.org forums for its long-term benefits to learning, apparently linked to Nerve growth factor. Highly speculative stuff, and it’s unclear whether the mushroom powder I bought was the right form to take (ImmInst.org discussions seem to universally assume one is taking an alcohol or hotwater extract). It tasted nice, though, and I mixed it into my sleeping pills (which contain melatonin & tryptophan). I’ll probably never know whether the $30 for 0.5lb was well-spent or not.

Accordingly, we searched the literature for studies in which MPH or d-AMP was administered orally to nonelderly adults in a placebo-controlled design. Some of the studies compared the effects of multiple drugs, in which case we report only the results of stimulant–placebo comparisons; some of the studies compared the effects of stimulants on a patient group and on normal control subjects, in which case we report only the results for control subjects. The studies varied in many other ways, including the types of tasks used, the specific drug used, the way in which dosage was determined (fixed dose or weight-dependent dose), sample size, and subject characteristics (e.g., age, college sample or not, gender). Our approach to the classic splitting versus lumping dilemma has been to take a moderate lumping approach. We group studies according to the general type of cognitive process studied and, within that grouping, the type of task. The drug and dose are reported, as well as sample characteristics, but in the absence of pronounced effects of these factors, we do not attempt to make generalizations about them.


The use of cognition-enhancing drugs by healthy individuals in the absence of a medical indication spans numerous controversial issues, including the ethics and fairness of their use, concerns over adverse effects, and the diversion of prescription drugs for nonmedical uses, among others.[1][2] Nonetheless, the international sales of cognition-enhancing supplements exceeded US$1 billion in 2015 when global demand for these compounds grew.[3]
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