Several studies suggest that memories can be pharmaceutically dampened. A few months ago, for instance, researchers showed that a drug called ZIP causes cocaine-addicted rats to forget the locations where they had regularly been receiving cocaine1. Other drugs, already tested in humans, may ease the emotional pain associated with memories of traumatic events. Indeed, the use of memory-altering drugs to treat addicts or victims of assaults, car accidents, natural disasters and terrorist attacks looks increasingly promising.


Many are alarmed by the prospect. As far back as 2003, the US President's Council on Bioethics issued a report that largely decried the use of such drugs2. Since then, journal articles and news stories have reiterated concerns that memory manipulators could interfere with the ability to lead true and honourable lives or could undermine a person's sense of identity.

The fears about pharmaceutical memory manipulation are overblown. Thoughtful regulation may some day be appropriate, but excessive hand-wringing now over the ethics of tampering with memory could stall research into preventing post-traumatic stress in millions of people. Delay could also hinder people who are already debilitated by harrowing memories from being offered the best hope yet of reclaiming their lives.

Various drugs are being investigated3,4. Propranolol, for instance — which is already approved by the US Food and Drug Administration to treat hypertension — may dull the emotional pain associated with the recall of an upsetting experience by interfering with the release of stress hormones that otherwise strengthen memories. Preliminary studies suggest that propranolol can inhibit the formation of traumatic memories even when taken a few hours after a distressing event5,6.

Given the close connection between memory and a sense of self, some bioethicists argue that instead of seeking a solution in a pill bottle, we should do the difficult but rewarding emotional work required to transform bad experiences into positive ones. They worry that giving people too much power to alter their life stories could ultimately weaken their sense of identity and make their lives less genuine2.

These arguments are not persuasive. Some memories, such as those of rescue workers who clean up scenes of mass destruction, may have no redeeming value. Drugs may speed up the healing process more effectively than counselling, arguably making patients more true to themselves than they would be if a traumatic experience were to dominate their lives. As psychiatrist Peter Kramer described in his 1993 book Listening to Prozac, some patients report feeling like themselves for the first time after taking antidepressants.

Some have also argued that memory-dampening drugs may inure users to the pain of others. For example, soldiers might be less inhibited to kill if they think they can pharmaceutically dissipate the emotional impact of their actions2. Yet we permit soldiers to use remotely operated drones even though these devices are likely to make some soldiers more willing to kill. If we seek to minimize soldiers' physical wounds, we should also address their emotional ones.

Underlying these concerns is an unjustified aversion to pharmaceutical methods of managing trauma7. Almost every media report on memory-dampening drugs delves into the ethical issues they raise. Yet the ethical implications of non-pharmaceutical approaches to memory dampening are generally ignored. For example, a non-pharmaceutical method of helping subjects forget a learned association between a visual cue and an electric shock was described in Nature last year8. Although the study received widespread media coverage, ethicists largely ignored it.

Until researchers uncover the cost, efficacy and side effects both of pharmaceutical and of non-pharmaceutical approaches to memory dampening, one should not automatically be deemed inferior to the other.

That said, in some contexts there are grounds for regulating the use of drugs to manipulate memory — particularly drugs that alter factual recall.

Take a scenario recounted by a US doctor in 2007 (ref. 9). The doctor had biopsied a suspected cancer patient and sent a tissue sample to a pathologist while the woman was still in the operating room. Thinking she was completely sedated, the pathologist announced a bleak prognosis over the intercom. The patient, who had received only local anaesthesia, heard the news and began to shriek, “Oh my God. My kids!” An anaesthesiologist standing by quickly injected her with propofol, a sedative that causes some people to forget what happened a few minutes before they were injected. When the woman woke up, she had no memory of hearing her prognosis. Although the anaesthesiologist's action was well-meaning, the patient probably had the right to decide whether to have her mind manipulated10.

Broad prohibitions, however, are unnecessary7.In most countries, existing law would already prohibit particularly egregious uses. For example, getting a witness drunk to prevent him from testifying in court has long been deemed an obstruction of justice by US judges. Pharmaceutically erasing a witness's memory for the same purpose would already be considered a crime.

Lawmakers could easily add new restrictions. For example, in cases that could endanger people's lives, such as when the only witness to a violent crime seeks to forget traumatic memories, physicians could be required to contact police before prescribing memory-dampening drugs.

Fear that the potential fruits of research may be prohibited or heavily regulated could deter researchers from pursuing studies on memory manipulation or funders from supporting them. Instead, researchers should be encouraged to explore pharmaceutical and non-pharmaceutical methods of helping people cope with trauma.