Researchers prove ‘fear’ neurons can be removed
TARGETING small numbers of “fear” neurons could erase traumatic memories and help people overcome drug addiction, research suggests.
But the technique has “huge” ethical implications, the Canadian scientist developing it has warned.
The research has echoes of science fiction movie Eternal Sunshine Of The Spotless Mind, in which an estranged couple erase each other from their memories.
In real life, the team of Dr Sheena Josselyn, from the University of Toronto, has succeeded in both activating and erasing fear-based memories in mice.
Previous research had highlighted collections of neurons known as “engrams” that fire in a particular pattern when a memory is created.
The Canadian researchers found certain neurons compete to be recruited to an engram for a fearful memory.
Of the millions of brain neurons, only a few were necessary to form a memory associated with fear.
By genetically removing the targeted neurons, a specific memory could be erased, without affecting other memories.
Further work in mice showed cocaine addiction could be overcome by wiping out emotional memories associated with taking the drug.
Speaking at the annual meeting of the American Association for the Advancement of Science (AAAS) in Boston, Dr Josselyn said: “Our findings suggest that one day it could be possible to treat people with PTSD (post-traumatic stress disorder) by erasing these traumatic memories.
“In these people, the memories are intrusive and disrupt their everyday lives.
“However, there could be potential downsides, especially when applied to people who would like to get rid of a ‘bad memory’ such as a messy break-up.
“If we erase the memory of our mistakes, what is to keep us from repeating them?”
She added: “There are huge ethical implications. Just because something is possible, does not mean that it should be done. Our studies provide a proof of principle, basically that erasing a memory is possible. However, our society needs to develop ethical policies...on this.”
In humans, it would not be appropriate to kill off brain cells in the same way, said Dr Josselyn.
Instead she envisaged a “missile-like drug” that could zero in on selected memory neurons and de-activate them.