Imagine that at the age of 15 you were violently sexually assaulted. Ever since, you have been unable to enter into a close relationship, as any intimate contact provokes strings of vivid nightmares and flashbacks during which you remember each moment of the attack in excruciating detail. At some point, you would likely visit a psychiatrist who would diagnose you with post-traumatic stress disorder (PTSD).

But what if you could go back to the hours after the episode and take pills that would make your memory of the event cloudy?

Memory researchers have recently begun to use medications known as beta-blockers, traditionally used to treat high blood pressure, in an attempt to prevent the onset of PTSD. According to the National Center for PTSD, the disorder is characterized by nightmares, flashbacks, difficulty sleeping, detachment and estrangement following the experience of “life-threatening events such as military combat, natural disasters, terrorist incidents, serious accidents or violent personal assaults such as rape.”

While findings of such memory manipulation research are still speculative, ethicists have begun to question how dabbling with the formation of memory might redefine what it means to be human. This research is particularly relevant to public concern following the release of such films as “Eternal Sunshine of the Spotless Mind” that present a science fiction view of memory erasure.

How could such a pill be explained? The research of James McGaugh, director of the Center for the Neurobiology of Learning and Memory at the UC-Irvine, has demonstrated that we are more likely to remember events that are emotionally arousing. Think about the morning of Sept. 11. The events of that morning — where you were, what you were doing, who you were with — may be crystal clear in your mind. If you could block the emotion, could you also block out the memory? “There is evidence that blocking the emotional arousal also blocks this emotion-mediated increase in recollection,” said David Speigel, professor of psychology and associate chair of the Psychiatry and Behavioral Sciences at School of Medicine here at Stanford.

Physicians have been “blocking the emotional arousal” of patients with high blood pressure for years through the use of drugs called beta blockers. According to Speigel, one commonly used drug, propranolol, “blocks activation of part of the sympathetic nervous system that would normally increase heart rate and blood pressure in response to

a stressor.”

Your sympathetic nervous system is normally responsible for activating the physiological flight-or-flight response that prepares you for dealing with stressful events — such as running away from a tiger or taking the MCATs.

Larry Cahill, a colleague of McGaugh’s at UC-Irvine, applied the use of propranolol to memory research. When he administered doses of the drug to a group of subjects, he found that the drug prevented the heightened recollection associated with the viewing of a gruesome story.

In patients suffering from PTSD, the heightened memory associated with emotional arousal “goes too far” according to Roger Pitman, a professor of psychiatry at Harvard Medical School. According to other research, PTSD could last a lifetime. Thus, medication that could reduce or eliminate PTSD could help thousands of people who are emotionally scarred from events.

Pitman’s research suggests that if a patient undergoes treatment with propanolol within the hours following a traumatic episode, negative memories would not be as deeply embedded in the brain. By extension, McGough suggests that the drugs could also be taken in anticipation of a disturbing experience, such as paramedics scraping bodies off the highway or a mother visiting the morgue to identify a dead son.

A recent article in The New York Times expressed concern that if the use of propanolol becomes routine, people who would not have developed PTSD will be taking the medication unnecessarily. However, neither McGaugh nor Pitman are concerned with this possibility because of the lack of serious side effects associated with the medication.

Even so, some find the manipulation of memory formation troubling.

While not wanting to appear insensitive to those suffering from PTSD, junior Erin Lashnits remarked, “I think that memories make up an important part of a person’s identity . . . even if the memories don’t change, you’re changing the intensity of that memory or of the reaction to an event. [The drug] has the potential to have much more serious complications with a person’s personality than just making life a little easier.”

Speigel said that he was “sympathetic” to such views, stating that “The real task is to refind yourself in the wake of the trauma, not pretend it did not happen.”

Such opinions raise questions of the value of suffering to human life, central to some religions, but researchers remain unfazed.

“The view is that we need to suffer because that is the nature of human nature,” responded McGough to such opinions. “[But] does anyone really believe that?” If we actually believe that, he continued, then we should let a soldier whose leg has been blown off “lie there and say that it is part of the human condition.”

Others make a distinction between physical and emotional suffering and argue that even if we already treat physical suffering with pain medications, for example, that by working through emotional pain we become stronger individuals.

In Pitman’s estimation, however, “a mental disorder is a physical disorder.” He said that he hopes that science fiction scenarios will not deter future scientists from pursuing research that could benefit a significant psychological condition.

McGough does not discourage ethical reflection about the applications of research into memory formation, yet wonders whether popular culture and science fiction movies, such as “Eternal Sunshine of the Spotless Mind” have sensationalized the actual research and benefits.

“[In my opinion,]” he added, “the whole thing is overblown.”