Neuroscientists use neurofeedback to erase fear in the brain

Posted on December 9, 2016

Photo: flickr

Imagine a person is terrified of dogs because they once suffered a terrible bite. Following long-established techniques, their psychologist might gradually expose them to dogs in a safe setting, until their fear gradually faded away. This “exposure therapy” can be effective but it has some serious drawbacks, including the fact that the person might at first find it traumatic to be close to dogs again.

There is a new study reported recently in Nature Human Behaviour that discovered a way to remove a person’s fear of dogs at a subconscious level, without the need for any traumatic exposure. The results revealed that neurofeedback can be used to unlearn a fear by pairing relevant non-conscious neural activity with a reward, such as money. It is an exciting breakthrough even though technical obstacles remain before this becomes a real-life treatment.

In Japan, Ai Koizumi and her colleagues at ATR Computational Neuroscience Laboratories in Japan trained 17 participants (11 men and 6 women) to fear two colourful grating patterns presented on a computer screen by repeatedly pairing the patterns with safe but unpleasant electric shocks. Toward the end of this session, participants’ electrodermal response (skin sweatiness) were measured and results confirmed that they now found them aversive. Researchers also scanned participants’ brains while they looked at these two patterns, so the researchers knew what neural activity tended to accompany the mental representation of each one. After the fear-induction process, one of the patterns (the “target”) was chosen as the learned fear to be removed, the other acted as a control.

Several sessions of neural feedback training were conducted for the participants over the next three days while the researchers monitored their brain activity. This involved the participants looking at grey grating pattern and then trying to use any mental strategy they liked to try to get a small disc on the screen to increase in size. If the participants succeeded, a small amount of money was rewarded to them.

This challenge was tough initially but gradually and subconsciously the participants improved at the task. Unbeknown to the participants, their success was dependent on their displaying a form of brain activity (hence why this was a form of neurofeedback training). To go into details, what made the disc grow was the participants’ visual cortex exhibiting neural activity previously associated with representing the target grating pattern. In other words, whenever the participants’ brains showed non-conscious neural activity related to the target feared pattern – which they did occasionally – the disc grew, and they were rewarded with money.

No experience of fear based on their electrodermal response or subjectively were shown, suggesting the fear-related brain activity was entirely non-conscious. Participants were quizzed after the training and shown no idea what had been going on at a subconscious level.

Of course the key test was what happened when, after the neurofeedback training, the researchers subsequently re-exposed the participants to the two colourful grating patterns. As hoped, the participants showed a much weaker fear response (again, based on their skin sweatiness) to the sight of the target grating, as compared with the control grating. In fact, the magnitude of this fear reduction was similar to that seen for conventional exposure therapy. The researchers also scanned the participants’ brains during this testing phase (as they had done during the fear-induction phase) and this showed that the participants’ amygdala activity was now lower in response to the target grating compared with the control grating. The amygdala is involved in fear processing so this provides more evidence that the fear-removal process had worked.

Researchers suggested – for example, by extrapolating from other people’s dog-related brain activity or by decoding dog-related brain activity based on showing our client subliminal dog images (I’m running with the dog example here but the same principles would apply whatever it is that a client feared). “Despite these challenges,” Koizumi and her colleagues concluded, “the present results hopefully represent an initial step towards a potential new avenue for treatment.”

To read the full article, please click on link below.


Source material from British Psychological Society