Scientists at Stanford University may have found a way to remove memories of traumatic events, at least in mice.
Classically, treating conditions associated with traumatic memories (such as post-traumatic stress disorder, or PTSD) involves a series of treatments that can be “grueling for the patient” or even “barbaric,” Gizmodo notes. Patients are induced to “recall the drama [that traumatized them] over and over and over in front of a shrink until, eventually, they learn how to deal with it," the site writes.
This kind of treatment often won’t prevent relapse, as patients learn to associate the technique with the psychiatrist’s office and then either can’t generalize it to the real world or associate it too strongly with a therapy setting, Nature reports.
But through her team's study, lead author Asya Rolls has found another technique she thinks might ease the pain.
Instead of traumatizing mice and then treating them with “therapy” (in a mouse’s case is simply re-exposure to previously threatening stimulus sans threat) the Stanford team tried tackling mouse trauma with a new, neurochemical approach.
Liz Klimas of The Blaze reports:
In her team’s research, Rolls trained mice to fear the smell of jasmine. Mice were conditioned to fear electrical shocks to their feet upon smelling the chemical, even when no shocks were administered. Some mice in the study continued receiving shocks. Others [exposed to the scent but] not receiving shocks eventually overcame their fear, but the researchers found when placed in a different cage, they relapsed at the scent. A third treatment group was given a drug that would block production of a protein in an area of the brain that stores traumatic memories — the basolateral amygdala. While sleeping, the mice were exposed to the jasmine. When the mice were awake, the researchers saw reduced fear when exposed to the chemical — even when they were transported to different cages.
In her announcement at the Society for Neuroscience meeting in New Orleans, La., Rolls said that protein synthesis drug would likely not be safe for use in humans, but that “existing anti-anxiety medications could potentially have similar effects when paired with sleep-based exposure therapy.”
During sleep, the mind is not rooted in any particular environment. So the effect of curbing traumatic memories in someone who is fast asleep wouldn’t be linked to any specific setting, such as a doctor’s office. This could protect a person from re-experiencing the trauma in other situation.
Roll’s study was inspired by studies earlier this year that showed how learning and memory were crucially affected by sleep. They used many of the same protien-based memory-manipulation techniques as a 2008 study by the Medical College of Georgia, in which researchers actually erased specific memories in mice.
Currently it’s not clear whether Rolls’ drug is actually erasing mouse memories or merely dulling the pain, though other sleep researchers are already proposing theories.
“I think it’s actually causing a reactivation of the same neurons that encoded the information during wakefulness,” says Gina Poe, a sleep researcher at the University of Michigan. Rolls’ drug, she suspects, “doesn’t allow the memory to be re-stored in the same way as it was before.”
Either way, researchers are excited by the implications of the Stanford study.
“We have an ethical obligation to study this because PTSD is so hard to treat,” Daniela Schiller of Mt. Sinai School of Medicine said. “It’s definitely promising.”
Rolls, too, says she thinks "this has huge potential," Science News notes.