Modifying memories: Is it ethical?

Recently, and far from Hollywood, medical researchers have begun to investigate the effectiveness of propranolol, a medication used to treat hypertension, in dampening memories that contribute to PTSD and its symptoms. Therapeutic outcomes from this research might include, for instance, starting a regimen of propranolol when a person first arrives in ER to be treated for traumatic injuries or for the effects of physical or psychological abuse. In 2004, however, the President's Council on Bioethics in the United States concluded that the predicted benefits of pharmacologically modifying negative memories would likely be far less than the harms. Psychotherapy was considered a better understood, less risky therapeutic measure.

But in 2007, the American Journal of Bioethics (AJB) published an article that re-ignited the debate. Michael Henry and his co-authors challenged the Council's position on the grounds that it was morally too conservative and that the predicted harms were hyperbolic and unjustified. The authors advocated preventive as well as therapeutic use of propranolol for PTSD. Preventive examples would include prophylactically providing the drug to individuals employed in violent or traumatic work, such as emergency first responders.

When a person encounters a serious threat, signals from the brain's amygdala reach the adrenal glands and adrenaline is released. This is part of our "fight or flight" response--blood vessels quickly constrict and respiration and heart rates speed up. For many years, people with certain heart problems have been prescribed the beta-blocker propranolol to staunch the release of adrenaline. Because the amygdala is part of the brain's limbic system that regulates emotions, it is hypothesized that propranolol may also help to block or dampen emotional reactions. This is relevant for PTSD because memory consolidation and storage can be affected by the intensity of accompanying emotion: the greater the negative emotion, the more resilient and powerful the memory.

I'd like to synthesize some pivotal thoughts from both sides of the debate, gleaned from articles published in bioethics journals. Hall and Carter, writing in the same issue of the AJB as Henry, favour using propranolol for memory modification or prevention, noting that people trying to cope with the disabling effects of PTSD may be finding temporary relief from excessive alcohol consumption. Alcohol can be a relatively inexpensive coping option when psychotherapy sessions must be paid privately or when insurance plans reimburse only a few sessions. Therefore, a fair assessment of propranolol therapy for PTSD must include a realistic comparison of its harms and benefits with the harms and benefits of other available strategies.

Other authors question the wisdom of using propranolol. First, our understanding of memory-making or memories themselves remains very limited. Most fear responses are normal and contribute to safety, and many people recover from them in a relatively short time. Do we really think that the drug's chemical properties can be refined enough so that it targets only seriously disabling memories? Bell, also writing in the AJB, reminds us that even now, medicine cannot predict accurately who will develop PTSD after a traumatic event. Moreover, will we be able to determine who will and won't benefit from prophylactic use of propranolol?

The second concern about medicating memories involves recognition that people's emotions are extremely important ethically because they relate to and reveal their personal values, conscience and self-identity. The fact that "Bob" feels rage, not just anger, about his partner's betrayal reflects how precious Bob considers their relationship and how deep has been his loyalty to "Joe." The deep guilt someone feels after exploiting her employer's goodwill affirms that she knows she acted wrongly and this matters a lot to her. Enduring discontent or content can reflect serious dissatisfaction or satisfaction about "the person I have become." Tampering with strong emotional responses may undermine our moral development, commitments and agency too much. This leads into the third concern about pharmacologically blunting or preventing emotion-laden memories.

Just as your emotions are meaningful to you, they are also meaningful to other people. Several writers in the articles I read worried about the possible effect of dulling or preventing negative emotional reactions to, for instance, being psychologically abused or sexually assaulted. Other people might not appreciate the seriousness of this behaviour if medicated victims* do not experience strong negative emotions. Victims' semantic memory, which focuses on the event's details or "facts," would not be affected. But their episodic memory, which is about the lived and embodied experience of the event, would be. Loss of individual emotional memories could change a society's expectations regarding the rights and duties of its citizens.

I've presented here some of the ethics-related complexities of using propranolol to prevent or treat traumatic memories. The researchers and ethics specialists whose work I read on this subject all seem to support efforts to increase the number of therapeutic options that clinicians can offer people seeking relief from PTSD's damaging symptoms. Propranolol may eventually prove to be one option, but so may other psychotherapeutic techniques.

* Some people prefer the term "survivor" to "victim." I use "victim" here to reflect the disabling symptoms of PTSD.

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Barbara Russell, bioethicist at the Centre for Addiction and Mental Health in Toronto, answers ethics questions that arise in the mental health and addiction fields. She is connected with the University of Toronto's Joint Centre for Bioethics and heads the neuroethics interest group of the Canadian Bioethics Society. She is also a contributing editor to the Journal of Ethics in Mental Health.

Do you have an ethics question for Dr. Russell? Submit questions to be considered for this column to CrossCurrents editor Hema Zbogar at hema_zbogar@camh.net. Please omit personally identifiable health-related information in order to respect people's privacy and follow privacy legislation.