Psychostimulants as cognitive enhancersThe use of uppers to help study for exams—an uncondoned practice that dates back decades—came under renewed scrutiny with a recent front-page story in the New York Times that highlighted the prevalence of the practice. More and more students appear to be taking stimulants to improve mental focus and to elevate test scores.

No surprise there, really. For many students, caffeine, energy drinks and concoctions such as No-Doz no longer suffice. And Ritalin and Adderall are well-ensconced as exemplars of aide-de-crams. The spotlight directed toward this class of drugs raises anew the prospect of whether “cognitive enhancers” should be freely available to improve performance.

At first glance, this question seems absurd. Why should controlled substances be accessible to perfectly healthy young people? Recess and Ritalin? Your family doctor would cut off this line of conversation immediately.

But,for the last few years, a group of scientists, clinicians and ethicists have mused on the big ‘what if’ as to whether drugs that enhance cognition, if accompanied by a benign side effect profile (what if, what if, what if), should be made freely available to whomever wishes to indulge in pharmacological self-improvement.

Our sister publication, Nature, was instrumental in initiating this debate in a commentary published in 2008 that suggested that psychostimulants should be available to the able-minded as long as they work and are safe. The article equated these drugs with “education, good health habits and information technology—ways that our uniquely innovative species tries to improve itself.” One of the article’s authors, John Harris, went even further and told me that he foresaw the possibility of these drugs eventually becoming available as over-the-counter medicines like aspirin.

Is there anything wrong with this picture? The problem relates to the inherent complexity of the brain and the imperfections of drug development. In part, it revolves around semantics. What, for one, does the term cognitive enhancement really mean?

For starters, is there really such a thing? In a Scientific American article that I wrote on this topic in 2009, I pointed out that “the complex mix of chemical signals, enzymes and proteins that collaborate to form a memory creates a self-regulating balance that resists tinkering unless disrupted by disease.” A hypothetical memory-enhancing drug that improves long-term memory might elicit an undesirable tradeoff in which working-memory (where you store a phone number) might be compromised. The same argument holds for attention-enhancing stimulants.

The equivalent of an aspirin tablet for mental acuity is a bit unlikely. The piece in the New York Times mentioned students whose performance soared on Ritalin and Adderall. True, ingesters of the amphetamine Adderall or the amphetamine-like Ritalin routinely report a perception of improved performance. Does the brain really work better on these drugs, though? The stimulant taker may think so in a drug-induced euphoria.

But are those gains real? That question has been addressed repeatedly since World War II, when these drugs were distributed widely to troops on both sides. Some studies have shown that, on some measures, such as reading and doing arithmetic, performance improved, but no more than chugging a double latte. Gains tend to come on rote, repetitive tasks. A significant mental challenge may require a flexibility in thinking that may actually deteriorate under the influence of an amphetamine. Perseveration—the tendency to mentally fixate—is occasionally an unwanted side effect. Imagine starting to study and spending the entire night exploring the contents of a single footnote.For some, moreover, the drugs can sometimes be addictive or can cause heart arrthymias.

This debate isn’t going away. At the very least, the medical marijuana folks will make sure that unconventional repurposing of drugs for new uses will continue to grace agendas in state legislatures and at bioethics meetings.

Unfortunately, the status quo as far as cognitive enhancement is unlikely to budge. The “one pill makes you larger” refrain will continue to echo with some scientists and fiction writers. But a drug that betters attention, memory or mental processing speed—and which does not cause seizures, strokes, addiction or manias—remains a tall order with our still limited grasp of the nuances of neuropsychopharmacology.

The much-vaunted polypill is a case in point. Distributing a medication that combines a statin, aspirin and compounds that lower blood pressure to anyone who reaches 50 candles would undoubtedly burnish public-health statistics. But a few of the individuals on this regimen would undoubtedly experience stomach bleeding from the aspirin and muscle weakness from the statin.

Cognitive enhancers will likely carry similar baggage. So a synthetic chemical with optimized pharmacokinetics and pharmacodynamics that will let you sail through the SATs or the MCATs will not be under evaluation by the FDA any time soon. The demand for such an elixir will undoubtedly persist. But, for the moment, Starbucks—or the pharmacies filling bogus ADHD scripts—are the most likely beneficiaries.

Source: Wikipedia Commons