Forget Something? We Wish We Could

'Therapeutic forgetting' helps trauma victims endure their memories.

6 min read

Remorse. Heartbreak. Embarrassment. If we could erase memories that haunt us, would we? Should we? Scientists who work with patients suffering from posttraumatic stress disorder (PTSD) are developing a new science that has been called "therapeutic forgetting."

But by erasing traumatic memories, are we changing the person? Are we erasing capacity for empathy?

Last year, the President's Council on Bioethics expressed concern that "memory numbing ... could dull the sting of one's own shameful acts ... allow a criminal to numb the memory of his or her victims.

"Separating subjective experience of memory from the true nature of the experience that is remembered cannot be underestimated," says the Council's report. "Do those who suffer evil have a duty to remember and bear witness, lest we forget the very horrors that haunt them?"

The research community is divided on this issue. "I think there's an ethical concern," says Mark Barad, MD, professor of psychiatry and biobehavioral sciences at the UCLA Neuropsychiatric Institute. "It's hard to estimate what's important about a memory, how the memory interacts with who we are, how it affects our ability to empathize.

"Philosophically, I'm on the side of extinguishing fear rather than blocking memory," Barad tells WebMD. "Given my experience with people with PTSD, we're talking about a very severe downside to blunting memory."

After all, would Holocaust survivors wish to blunt their memories? Would that be good for society? Or should people have the freedom to decide if they want horrible memories softened?

James McGaugh is a pioneer in the neurobiology of learning and memory. He directs the Center for Neurobiology of Learning and Memory at the University of California at Irvine.

For several decades, he has performed numerous animal and human experiments to understand the processes involved in memory consolidation. He believes strongly in the work being done to help people suffering from PTSD.

An event becomes a strong memory, a traumatic memory, when emotions are high, he explains. Those emotions trigger a release of stress hormones like adrenaline, which act on a region of the brain called the amygdala -- and the memory is stored or "consolidated," explains McGaugh.

Current studies have focused on a drug called propranolol, which is commonly prescribed for heart disease because it helps the heart relax, relieves high blood pressure, and prevents heart attacks. "Hundreds of thousands, millions of people take this drug now for heart disease," he tells WebMD. "We're not talking about some exotic substance."

Studies have shown that "if we give a drug that blocks the action of one stress hormone, adrenaline, the memory of trauma is blunted," he says.

The drug cannot make someone forget an event, McGaugh says. "The drug does not remove the memory -- it just makes the memory more normal. It prevents the excessively strong memory from developing, the memory that keeps you awake at night. The drug does something that our hormonal system does all the time -- regulating memory through the actions of hormones. We're removing the excess hormones."

The first to treat PTSD patients with propranolol was Roger K. Pitman, MD, a psychiatrist at Massachusetts General Hospital and Harvard Medical School. He'd just as soon forget the term "therapeutic forgetting."

"We think of PTSD as an exaggeration of the emotional response to trauma," Pitman tells WebMD. "Something so significant, so upsetting, so provocative has happened that there has been a rush of stress hormones, the hormones that act to burn a memory into the brain, to the point that the memory becomes maladaptive. Our theory is that the adrenaline rush is burning the memory too deeply."

Timing is critical. Once PTSD has developed, it's too late to change stored memory, says Pitman. "It's important to intervene soon enough to affect memory consolidation."

In his study, Pitman gave propranolol to emergency room patients within six hours of a traumatic event. He found that six months later they had significantly fewer signs of PTSD.

"It's not that they couldn't remember the accident," McGaugh explains. "They couldn't remember the trauma of the accident. They didn't have as many symptoms of PTSD. It's a very important distinction."

Propranolol was used to treat PTSD, with fairly good success, in a small study treating sexually abused children. It's also prescribed for specific phobias like public speaking, says Jon Shaw, MD, a PTSD expert and director of child and adolescent psychiatry at the University of Miami School of Medicine.

The drug "erases the acute emotionality of the situation so people can function," he tells WebMD. "It's the "deer in the headlights phenomenon. The intense emotionality paralyzes and interferes with the memory-integration process."

When someone has been exposed to trauma, "the more intense the emotion is, the more fragmentation there is in the memory," Shaw explains. "They don't have a realistic, coherent narrative of what happened. Some aspects are heightened, others are diminished. They're left with an overwhelming sense of the event, yet they can't really piece it together, so they can't really achieve mastery over it. They lose their rational ability to understand it."

Propranolol could be used to "immunize" someone against trauma only in a minority of cases, says Pitman. "We can't use it in combat because soldiers need adrenaline to fight. But if they have just returned from a terrible battle, and they're traumatized, then it has potential application."

McGaugh has no problem with this use of propranolol. After all, "every pill that goes into your body does something to change you," he tells WebMD. "Antidepressants, antipsychotics -- all of these are designed to help people function better. Society crossed that bridge years ago."

He offers a more graphic example: If a soldier is wounded on a battlefield, is he left to suffer so that he can learn from that experience? "Imagine it: Do you just let him lie there and bleed to death because he needs to suffer the consequences of having killed another human being in battle? We give him first aid, pain medication, we do everything can. But if he's having an emotional disturbance because of that trauma, we can't do anything about that because that would change the nature of who they are. Doesn't losing a leg change the nature of who they are?"

Yes, there's possible downside to propranolol, McGaugh tells WebMD. "There is a chance that another memory could be affected. If the person gets a call and learns that they have a new grandchild during that time, they might not have quite as strong an experience of that news. Everything comes with a small price. But these are not amnesia pills."

But can a pill take away remorse? "That's silliness," says McGaugh. Will college men rape women students because they don't feel remorse? "Good grief. We're not talking about failing to remember what happened. We're talking about a drug that could prevent memory from taking over your existence, as PTSD does.

"We have people from World War II, the Korean War, the Vietnam War, still living with the horrors of that remembered trauma. If you asked any of these people if you would want to have PTSD or not, what do you think their answer would be?"

Published April 9, 2004.