Can a high-tech treatment help combat some of our oldest fears?
“Scientists have raised hopes for a radical new therapy for phobias,” The Guardian reports.
Brain scanners were used to identify brain activity pinpointing when people are most receptive to the “rewriting” of fearful memories. The scanners used functional MRI(fMRI) technology to track the real-time workings of the brain.
It’s already known that combining gradual exposure to a fearful stimulus, known as exposure therapy, sometimes with a reward, may re-condition the brain and reduce the fear. For example, a person with a phobia of spiders may first be shown pictures of spiders before eventually being exposed to actual spiders.
So this experimental study aimed to see if it was possible to get the same effect subconsciously, without direct exposure.
The research included 17 healthy volunteers who had a “fear condition” induced by being given sudden electric shocks while simultaneously being shown coloured patterns. This then lead them to fearfully responding when they were shown the same patterns again.
They then re-conditioned this response by analysing the participants’ brains with fMRI to estimate the optimal “receptive window” and giving them a small monetary reward while showing the same patterns. They showed that this was successful and on re-exposure their fear was reduced.
While interesting, this was a highly artificial scenario in a very small number of healthy people. It is far too early to say whether this approach would be effective in the long-term.
Where did the story come from?
The study was carried out by researchers from a number of institutions including ATR Computational Neuroscience Laboratories and Nagoya University both in Japan, Colombia University, and the University of Cambridge.
Funding was provided by the Strategic Research Program for Brain Sciences supported by the Japan Agency for Medical Research and Development (AMED), the ATR entrust research contract from the National Institute of Information and Communications Technology, and the US National Institute of Neurological Disorders and Stroke of the National Institutes of Health.
This research has been presented accurately in the UK media. The Guardian provided a good explanation of the study methods and findings, while also stating some of the limitations.
What kind of research was this?
This was an experimental study in healthy volunteers to see whether it is possible to condition people against their fear memories and responses by issuing rewards.
As the researchers explain, the concept that fear can be reduced by combining the fearful with a reward or something non-threatening, has already been established. This approach is often referred to as exposure therapy. This can be included in a more comprehensive cognitive behavioural therapy (CBT) form of counselling.
However, some people are unable to tolerate even limited exposure to stimuli they find frightening.
It also remains unclear whether you need to give explicit exposure to the fear for this reward process to work. The researchers’ newly developed approach uses a technique called fMRI (functional magnetic resonance imaging) decoded neurofeedback (DecNef).
DecNef combines brain scanning technology with a sophisticated computer algorithm “trained” to recognise certain patterns of brain activity, when people are thought to be most receptive to rewards to counter fear.
This means the person doesn’t have to be consciously re-exposed to the fearful stimulus.
While this method is a good way of testing the possible effects of such therapies it can’t prove that these methods would be safe and effective in people with genuine disorders, such as PTSD.
What did the research involve?
The researchers recruited healthy volunteers to take part in the study.
The experiment was split into stages which are as follows:
This part of the experiment was to establish fear. In this case the researchers chose to establish a fear of being shown red and green patterns by pairing this with a tolerable electric shock. Blue and yellow patterns were used as control stimuli.
Neural reinforcement (performed three times)
This stage was conducted for three consecutive days and aimed to induce brain activity for the red and green patterns even when the person wasn’t exposed to or actively thinking about the fearful stimuli.
If brain activity patterns associated with the fearful stimuli were induced then the participants were given a monetary reward.
Following the last neural reinforcement, a test was performed to measure the fear response when again directly exposed to the fear and control stimuli.
What were the basic results?
Seventeen healthy volunteers entered the trial having successfully established a fear response to the stimuli.
On testing after neural reinforcement, when re-shown both the fearful (red/green) and control (blue/yellow) stimuli, the brain’s fear response to the red/green patterns was actually now significantly less than the control stimuli.
This suggested DecNef had been successful – fear towards the target stimuli had been reduced by pairing the fearful brain activity with a reward, effectively over-turning the previous fear conditioning.
The size of the effect was said to be similar to that seen with standard fear exposure methods (such as pictures of spiders, etc), but in this case it was achieved without the participants actually being made aware of the fearful stimulus.
How did the researchers interpret the results?
The researchers conclude that they have been able to show that fear can be reduced by pairing rewards with the activation patterns in visual cortex that are associated with the fearful stimulus, while participants remaining unaware of the content and purpose of the procedure.
They suggest: “This procedure may be an initial step towards novel treatments for fear-related disorders such as phobia and PTSD, via unconscious processing.”
This experimental study assessed whether it is possible to counter-condition people against their fear memories by using reward without actually having to re-expose the person to the fearful stimulus.
The researchers conclude that they have shown this can be done, all with participants remaining unaware of the content and purpose of the procedure. They further suggest the procedure may be an initial step towards novel treatments for fear-related disorders such as phobia and PTSD, via unconscious processing.
While these findings show promise, there are some key limitations, the main one being the small number of healthy participants who had fear to colours induced by giving them tolerable electric shocks. This was also an artificial scenario. The “fear” or threat was very mild, compared to the threats people may fear or have experienced in real life.
The exposure in the form of different coloured lines was also very basic and simple to reproduce compared to complex and multidimensional real-life fears and traumas. As such we cannot know if the same findings would be seen in people with complex disorders such as PTSD.
Also, as this was an experiment with no follow-up period, we do not know if this conditioning against fear is long lasting. Much more research would be needed to confirm these findings.
It’s normal to experience upsetting and confusing thoughts after a traumatic event, but in most people these naturally improve over a few weeks.
You should visit your GP if you are still having problems about four weeks after the traumatic experience.
Similarly you should contact your GP if you find that a phobia is significantly adversely affecting your quality of life.