Johns Hopkins University School of Medicine researchers have discovered that by removing a protein from the region of the brain involved in recalling fear (the amygdala), using drugs and behavioral therapy, they can permanently delete traumatic memories for such conditions as post-traumatic stress disorder.

Richard L. Huganir, Ph.D., professor and director of neuroscience at the Johns Hopkins University School of Medicine and a Howard Hughes Medical Institute investigator, and his team used sound to cue fear in mice, and observed that certain cells in the amygdala conducted more current after the mouse was exposed to a loud, sudden tone.

Zeroing in on those specific cells, he found temporary increases in the amount of particular proteins — the calcium-permeable AMPARs — within a few hours of fear conditioning. The increases peaked at 24 hours and disappeared 48 hours later.

So could they remove the fear memory by combining behavior therapy and protein removal? They also found that cells lacking this chemical modification of GluA1 recovered fear memories induced by loud tones, whereas littermates that still had normal GluA1 protein did not recover the same fear memories. Huganir suggests that drugs designed to control and enhance the removal of calcium-permeable AMPARs may be used to improve memory erasure.

“This may sound like science fiction, the ability to selectively erase memories,” says Huganir. “But this may one day be applicable for the treatment of debilitating fearful memories in people, such as post-traumatic stress syndrome associated with war, rape or other traumatic events.”

The study is described in an open-access paper in Science and was funded by the National Institutes of Health and the Howard Hughes Medical Institute.