Scientists Pinpoint a Chemical That Can Delete Bad Memories

Monday, 06 November 2017 - 7:05PM
Neuroscience
Monday, 06 November 2017 - 7:05PM
Scientists Pinpoint a Chemical That Can Delete Bad Memories
Wikimedia Commons/Nicolas P. Rougier
Eternal Sunshine of the Spotless Mind was a quirky sci-fi movie with a core idea that most people on Earth can appreciate: what if we were able to simply erase unwanted memories, allowing us to enjoy the world without constantly remembering all the times we've fought with a partner, endured a messy break-up, or had to watch Elijah Wood attempt to seduce someone we still have feelings for?

A team of scientists from the University of Cambridge now believe that they've found a key chemical that's present in the human brain which allows us to filter out, suppress, and ultimately discard unhappy memories. And according to the study they've published, while this chemical is present in all our heads, some of us have more of it than others.

A deficiency can make it more difficult to forget things that we don't want to remember, which may be why it's so hard to escape negative thoughts and memories when trapped in the middle of a bout of depression.

The chemical in question, gamma-aminobutyric acid (more commonly known simply as GABA) works in a bizarre way. GABA is used to send messages between different nerve cells within the brain, but at the same time, it also dulls your memory of painful events.

When a nerve cell secretes GABA, it has the effect of suppressing other cells around it, meaning that they can't send messages through the brain. Essentially, GABA impedes recall of negative memories, so that when the brain is functioning normally, it becomes harder and harder to remember things that have gone wrong, while our memories of happier times stay intact.



The scientists involved in studying GABA came up with a novel way of figuring out what was going on within their test subjects' minds. In order to figure out how the brain manages to delete unwanted information (rather than just simply letting memories fade over time), participants were asked to learn to pair different words together, and then were told to actively try and forget some of these pairs - or otherwise stop thinking about their associated words) in another, later stage of the experiment.

While this was going on, the participants' heads were scanned, and the scientists noticed the heightened levels of GABA within their brains, hinting that this chemical compound has an important role in forgetting. As it turns out, it is possible to avoid thinking about something, even if it may feel difficult to try and force yourself to forget that embarrassing time you made a fool of yourself in front of your crush.

Having less GABA present in the brain appears to make it more difficult to forget anything, especially negative thoughts. It's therefore believed that this chemical might be connected to the self-depreciating thought cycles that those suffering from depression, schizophrenia, and anxiety disorders may be forced to endure.

According to study co-author Taylor Schmitz:

Opening quote
"The environmental and genetic influences that give rise to hyperactivity in the hippocampus might underlie a range of disorders with intrusive thoughts as a common symptom."
Closing quote


If ever you find yourself suffering from one of these mental disorders, and you simply can't see any joy or light in your life as you look back over the past few years, it's worth remembering that your mind may not be entirely trustworthy - a lack of GABA may lead to a colored view of the world that focuses too strongly on the negative.

The good news here is that if GABA is proven to be effective in helping us to forget things, scientists may be able to explore new methods of stimulating the release of this chemical in order to help the brain function in a healthy fashion. Soon, we may get the chance to enjoy a world in which alcohol isn't the only drug that people rely on to drown out bad memories.
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