Think of your favorite elementary school teacher, that time you broke your glasses in fourth grade or your college dorm room. Those images may evoke feelings of love, embarrassment or excitement. Beneath those feelings are tangible, microscopic connections between the long arms of your neurons called dendritic spines.
Because memory has a physical parallel in the brain it can, in theory, be disrupted. While we’re not close to erasing our memories of an old love affair, or even a traumatic event, a new study has found away to disrupt memory formation of a different kind of trauma, methamphetamine addiction.
Memories formed while high don’t chemically solidify like memories formed while sober, according to Florida-based Scripps researcher Courtney Miller. That instability leaves the protein connections that hold the memory vulnerable to destruction. Miller and her colleagues found a protein, called blebbistatin, or more familiarly as blebb, that can interfere sufficiently to erase the memory, Michael Miller reports at the Washington Post:
The idea might be scary, Miller admitted, “but what it really looks like is that [blebb] kind of goes in with a scalpel and takes out the memories that are associated with methamphetamine and methamphetamine alone.”
The Scripps Research Institute say their discovery brings them closer to a new therapy. “We now have a viable target and by blocking that target, we can disrupt, and potentially erase, drug memories, leaving other memories intact,” said Miller. “The hope is that, when combined with traditional rehabilitation and abstinence therapies, we can reduce or eliminate relapse for meth users after a single treatment by taking away the power of an individual’s triggers.”
In 2013, the team made the surprising discovery that drug-associated memories could be selectively erased by targeting actin, the protein that provides the structural scaffold supporting memories in the brain. However, the therapeutic potential of the finding seemed limited by the problem that actin is critically important throughout the body — taking a pill that generally inhibits actin, even once, would likely be fatal.
In the new study, Miller and her colleagues report a major advance — the discovery of a safe route to selectively targeting brain actin through nonmuscle myosin II (NMII), a molecular motor that supports memory formation.
Erasing memories of drug addiction is the first pharmaceutical option for meth and other stimulant addiction. While disrupting the memory can’t take away neurotransmitter imbalances or care the physiological or psychological reasons someone may use, it could help recovering addicts remove triggers from their lives, according to Popular Science:
This has proved extremely difficult for researchers and patients alike, as even with the best rehabilitation therapy and the most supportive friends and families, many addicts of psychostimulant drugs–methamphetamine, cocaine, and MDMA — relapse soon after therapy ends, often because the memory of the drug’s effect is too strong for that person to resist.
Eliminating triggers may be enough for addicts in recovery to stay drug-free. While Blebb does not mess with memories formed without the presence of meth, so in theory, only those related to drug use would be impaired.
But, this study has only been tested in mice so far. Mice, obviously, cannot report what aspects of those memories were changed or how. Will the erasure feel like an hours long black hole to a human? Will anything that happened during the use of the drug be spared? For some addicts that could mean losing large swathes of time that coincide with other important memories they might want to keep.
And it’s extremely difficult to get over the fear factor of losing one’s memory, bad or good, Miller writes:
Normally, the idea of losing our memories would seem scary. Amnesia is a terrifying and still baffling affliction. Alzheimer’s is, in many ways, the scourge of our modern age. But the scientists behind this procedure believe their work has the potential to revolutionize drug addiction treatment, possibly enabling millions of American drug addicts to literally forget the triggers that can otherwise lead to a life of painful relapses and, in some cases, a fatal overdose.
Our ability to consciously recover and relive our memories is an important part of our understanding of human consciousness. People who are in the early stages of recovery are likely under some emotional and psychological duress. Offering them a permanent treatment with significant side effects may be unethical. But, as Miller’s study notes, meth memories are vulnerable for ever. There appears to be no critical window for an addict to act on the option.
Meredith Knight is a contributor to the human genetics section at the Genetic Literacy Project. She is a freelance science and health writer based in Austin, Texas. Follow her on twitter: @meremereknight