Would you let your child get on a bus driven by someone on mind-altering drugs? What about having an operation conducted by a surgeon taking stimulant pills? Unappealing at first glance; however would your opinion change if you knew those drugs made the driver less likely to crash, and the surgeon better able to keep a steady hand?

Drugs that help people with brain and neuropsychiatric conditions improve concentration, planning and memory, or reduce impulsive and risk-taking behaviours, are increasingly finding their way into the hands of healthy people who want to study harder, work better, cope under stress and keep going during night shifts. And the use of these so-called “smart drugs” is set to grow in our increasingly competitive world, according to a report published late last year by four UK scientific academies.

"We are living for longer, working for longer and driving for longer," says Barbara Sahakian, Professor of Neuropsychology at the University of Cambridge, UK. "Perhaps if people had access to safe cognitive enhancing drugs, they would be at less risk of losing their attention in critical situations, and maybe we'd have more inventions, faster medical discoveries, safer transport and bigger economies."

While Sahakian and some of her colleagues believe chemically induced cognitive enhancement is worth exploring as a way for people to fulfil their potential, others worry about the long-term consequences, both to our health and our personalities. There are ethical considerations, too. If cognitive enhancers make the drivers and pilots to whom we entrust our lives less likely to crash, should taking them be a condition of employment? If popping pills can make completing mental challenges easier, how will that affect our sense of achievement and self worth? Are students who take cognitive enhancers to get better grades and access to top universities cheating, and will those not taking them feel obliged to do so to keep up?

Those that use smart drugs swear by them. "I probably gained nine or ten per cent in my exam and essay marks due to being able to focus and work more effectively," says John (not his real name), who took the narcolepsy treatment modafinil and the cognitive disorder drug piracetam in the final year of his politics degree course at Warwick University, UK.

He is by no means alone. While accurate data on the use of cognitive enhancers is lacking, there have been a few small surveys. Sahakian estimates 16% of US students are taking "study buddies", while a poll of students at Oxford University carried out last year, found 7% had tried them.

In the academic world, the phenomenon reaches both the top and the bottom of the tree. A 2008 online survey carried out by the journal Nature found that one in five readers had taken the anti-hyperactivity drug Ritalin, narcolepsy treatment modafinil, or beta blockers for non-medical reasons to stimulate focus, concentration or memory. Smart drugs have even reached primary school, with some US doctors now prescribing Adderall – amphetamine salts used to treat ADHD and narcolepsy – to healthy children from low-income families purely to improve academic performance.

Doors of perception

Shift workers, truck drivers, pilots and doctors are also known to take cognitive enhancers. Stimulant use has long been commonplace in the military, from Incans given coca leaves before battles to Allied soldiers using amphetamines during World War Two, and British, French and US troops using modafinil in more recent conflicts. In his book Mind Wars, Jonathan Moreno describes extensive recent research by the US Defense Advanced Research Projects Agency (Darpa), including experiments into the use of beta blockers to reduce stress hormones.

Some argue the development of new, more effective cognitive drugs, as well as ageing working populations and greater competition for work all point towards their use becoming more widespread in future. "Use on college campuses and even in high schools has become increasingly common and normalised," says Anjan Chatterjee, a neuroscentist at the University of Pennsylvania. "Students think of these as study aids in the same way as someone might drink coffee before work. As young people who are getting used to thinking about cognitive enhancement in a non-medicalised way get older it is likely to just become a normal part of how we approach the world."

Whether such predictions are borne out will depend on perceptions of whether cognitive enhancers work. "I take modafinil if I need a short-term boost of focus or if I need to revise for exams," says John. "Time passes quickly because you are working so hard and effectively, and when you go home you can remember absolutely everything. It also increases your alertness and awareness like a kind of turbo-charged caffeine only without the jitters, withdrawal and tolerance build up. Piracetam helps me think more clearly, focus and speak more articulately. I wouldn't say I've had any noticeable side effects."

But such anecdotal reports cannot be verified, and could be attributed to placebo effects. To date, there have been no large, long-term studies of cognitive enhancers. Last December, bioethicist Eric Racine and colleagues at the Institut de Recherches Cliniques de Montreal, Canada, published a report arguing that physicians should refuse to prescribe cognitive enhancers to healthy people. It highlighted risks of addiction, cardiovascular problems and psychosis associated with stimulants. "We don't really know what the long-term health implications of taking these drugs are for healthy people," says Racine.

Small studies have been carried out, though, some of which suggest there could be positive effects. Ritalin was shown to improve short-term, or working, memory and planning abilities in a study on 28 healthy young men in 1996. Tests carried out on 18 pilots at Stanford University found those given the Alzheimer's disease drug Aricept for 30 days were better able to retain complex aviation tasks learnt on a simulator than those given placebos. The authors said the drug likely improved working memory function by boosting levels of the neurotransmitter acetylcholine.

Tests published by Sahakian in 2003 found modafinil improved planning, pattern recognition, reaction times and reduced impulsive reactions in healthy people. And last year Sahakian and Ara Darzi of Imperial College London, found that doctors who had been deprived of sleep for one night showed improved working memory, planning, mental flexibility and reduced impulsive decision-making when they were given modafinil. Psychologists have also found study participants given Piracetam performed better in verbal memory tests after two weeks of taking the drug.

Memory jog

However, taken as a whole the evidence is mixed. Other, albeit less frequently reported, studies have shown little or no effects. In a 2010 review Claire Advokat, Professor of Psychology at Louisiana State University, found that stimulant drugs such as Ritalin might improve memory retention but "may actually impair performance of tasks that require adaption, flexibility and planning". Scientists at the University of Pennsylvania led by psychologist Irena Ilieva found volunteers given Adderall performed no better in 13 different cognitive ability tests, when compared to those given placebos. Interestingly, however, they did find improvements in some tasks for participants starting from a low baseline, and suggestions that those with two copies of a gene variant associated with higher levels of dopamine actually performed worse when given the drug.

"There might be some healthy people who see improvement in some functions in response to a drug and others whose performance might deteriorate with the same dose," says Mitul Mehta, a senior lecturer at Institute of Psychiatry, King's College London. Brain scans he carried out found those with the lowest working memory capacity to begin with improved the most when taking Ritalin. Another study, led by Martha Farah, Director of the Center for Neuroscience & Society at the University of Pennsylvania, found that Adderall could boost creativity for those who were not very creative to start with, but had no effect or even a negative impact in volunteers of around-average creativity.

This variability in effects can at least in part be explained by the fact that these drugs either boost or curb levels of circulating neurotransmitters, the chemicals that relay signals between nerve cells in the brain. Animal studies show that both very low and very high levels of dopamine in the prefrontal cortex can impair working memory, and that optimal performance comes somewhere between these extremes. "It's like traffic," says Mehta. "If there isn't much traffic around and you increase the speed of cars, things flow quicker. But if you do so in heavy traffic you get traffic jams."

Ilieva and others have also found that study participants falsely believed that the cognitive enhancers they were given had a big impact on their performance. This could explain the gap between the modest effects suggested by studies which find benefits and some of the glowing anecdotal reports.

Identity issues

So if most cognitive enhancers have only mild-to-moderate transient effects, can society leave it up to individuals to make their own judgements about the potential risks and benefits? No, argues Sahakian. In an article published in Nature in 2007, she and Sharon Morein-Zamir point out that increasingly sophisticated smart drugs targeted to a person’s genetic make-up could have large effects in future. Therefore, they argue, it is vital to consider the ethical implications now.

One concern is that using cognitive enhancers as a shortcut to success will threaten personal satisfaction in achievement, reduce the need for character-building effort and weaken our sense of identity. "As the power to transform our native powers increases, both in magnitude and refinement, so does the possibility for self-alienation – for losing, confounding, or abandoning our identity," wrote the authors of Beyond Therapy, a 2003 report by the US President's Council on Bioethics.

But cognitive enhancers are hardly unique in altering identity. The same could be said, for example, of improved nutrition and family planning. "Smart drugs may be character-changing," says John Harris, Professor of Bioethics, and Director of the Institute for Science, Ethics and Innovations, University of Manchester, UK. "But then so are many things, such as education, so in a free society it is for people to weigh that up and decide whether it's a desirable course of action."

Another objection is that, as with other new technologies, not everyone is likely to have equal access to cognitive enhancers and their benefits. People who currently use them are thought to be overwhelmingly from middle and high-income groups. This leads to fears that it will become even harder for those from low income backgrounds to get into the best schools, universities and jobs. However, as with the identity issue, a lot of other things that underline existing inequalities are accepted in most advanced societies. "Most people accept that in wealthier communities children get all kinds of tutoring and other advantages that allow them to get into better schools and greater opportunities later on," says Chatterjee.

John, the Warwick University student, doesn’t feel his use of the drugs is giving him an unfair advantage. "I don't see it as cheating. I take them to better myself and learn more, not to beat other people," he says.

Under pressure

Then there is the question of whether workers should be coerced into taking smart drugs to improve job performance. Again, Harris says the issue is hardly unique to cognitive enhancement. "You can't drive a car unless you pass a driving test, and that's a form of coercion, but we approve of it because we want safety. There might well be situations in which coercing people to take drugs is justified to enhance safety, such as keeping long-distance drivers awake or steadying the hands of surgeons."

What about indirect coercion, feeling the need to take smart drugs because competitors are doing so? While 86% of those who responded to the 2008 Nature survey said access should be restricted for healthy children under the age of 16, a third said they would feel pressure to give the drugs to their children if their fellow pupils were taking them.

“Peer-pressure coercion to take them is a worry and probably undesirable," admits Harris. "Yet such pressure is endemic in our society. Some people feel pressure to start work very early and not go home until the boss has gone. In my view the alternative of banning their use would be more undesirable and an even greater infringement of liberty."

The legal status of different cognitive enhancers varies in different countries. But the legality is of little relevance as customers turn to internet pharmacies to obtain them. "My view is that we should recognise people are already doing this but they are doing so in a very unsafe manner, buying them online and doing so without medical supervision," says Sahakian. "So it would be sensible for people to have access to safe, effective cognitive enhancers, but long-term safety studies are needed, and then perhaps people could do it in consultation with their GPs."

It's a call echoed by the joint UK scientific academies report which states: "Gaps in our knowledge could be addressed by studies on the long-term impacts of enhancements on the individual both in terms of efficacy and harm." Yet there are no signs that such research is likely to begin any time soon. Regulatory authorities such as the US Food and Drug Administration and the European Medicines Agency are set up to evaluate the effects of treatments on disease and disorders, not healthy people. Neither large pharmaceutical companies nor public funding bodies are likely to put forward the necessary funds because of the stigma attached to promoting the drug use to healthy people.

Policy makers are able to ignore the issue while levels of use remain low, and the effects are relatively mild. But a do-nothing approach is likely to become unsustainable if, as predicted, taking cognitive enhancers becomes normalised and the drugs become more potent. When that time comes, says Sahakian, developing laws and policies that deal with the ethical challenges, and allow individuals to balance potential benefits and costs will be much easier if we have data from larger studies into the effects of these drugs. The question is who would be willing to carry these tests out.

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