London: Scientists have discovered a way to remove specific fears from the brain, using a combination of artificial intelligence and brain scanning technology, an advance that may lead to new treatments for conditions such as post-traumatic stress disorder (PTSD) and phobias.
Currently, a common approach is for patients to undergo aversion therapy, in which they confront their fear by being exposed to it in the hope they will learn that what they fear is not harmful. However, this therapy is unpleasant. Researchers from the University of Cambridge in the UK have found a way of unconsciously removing a fear memory from the brain. They developed a method to read and identify a fear memory using a new technique called 'Decoded Neurofeedback'.
It used brain scanning to monitor activity in the brain, and identify complex patterns of activity that resembled a specific fear memory. In the experiment, a fear memory was created in 17 healthy volunteers by administering a brief electric shock when they saw a certain computer image. When the pattern was detected, researchers over-wrote the fear memory by giving their experimental subjects a reward.
"The way information is represented in the brain is very complicated, but the use of artificial intelligence (AI) image recognition methods now allow us to identify aspects of the content of that information," said Ben Seymour from the University of Cambridge. "When we induced a mild fear memory in the brain, we were
able to develop a fast and accurate method of reading it by using AI algorithms," said Seymour.
"The challenge then was to find a way to reduce or remove the fear memory, without ever consciously evoking it," he said. "We realised that even when the volunteers were simply resting, we could see brief moments when the pattern of
fluctuating brain activity had partial features of the specific fear memory, even though the volunteers were not consciously aware of it," he said.
"We decided to give subjects a reward - a small amount of money - every time we picked up these features of the memory," he said. Researchers repeated the procedure over three days. The volunteers were told that the monetary reward they earned depended on their brain activity, but they did not know how. By continuously connecting subtle patterns of brain activity linked to the electric shock with a small reward, the scientists hoped to gradually override the fear memory.
They then tested what happened when they showed the volunteers the pictures previously associated with the shocks. Such a treatment could have major benefits over traditional drug based approaches. Patients could also avoid
the stress associated with exposure therapies and any side-effects resulting from those drugs. The study appears in the journal Nature Human Behaviour.