Grant: CIHR Fellowship

Can 'hardwired' fear responses, e.g. for spiders and snakes, be reprogramed unconsciously in the human brain? Currently, exposure therapy is amongst the most effective treatments for anxiety disorders, but this intervention is subjectively aversive to patients, and rates of premature attrition have been reported to be as high as 70%. We developed a fully unconscious method to bypass the unpleasantness in conscious exposure using functional magnetic resonance imaging (fMRI) neurofeedback. Using this method, the similarity between the current brain activity and the brain representation of a feared object is computed in real-time and fed back to participants. Over the course of multiple trials, participants learn to generate brain patterns increasingly similar to the pattern of the feared object. I have previously shown that this intervention leads to a decrease in physiological fear responses without exposing patients to feared objects. Despite these promising findings, we could not observe long-lasting changes in fear reports probably because we did not have the technology to target all the relevant brain regions. Now, recent developments in machine learning allow to target whole-brain representations, which might be necessary to achieve clinically significant changes. I will conduct a randomized control trial with patients diagnosed with 2 specific animal phobias. In a double-blind fMRI neurofeedback protocol, participants will be trained to activate the whole-brain neural representation of one of the two feared animals, while the second animal will act as a control. We hope to observe a specific decrease in clinical symptoms, physiological fear responses and behavioural avoidance of real animals, for at least 6-8 months. Combining our unique unconscious fMRI method with in-scanner virtual reality may eventually extend our approach to other forms of fear, and particularly to post-traumatic stress disorders, which still present a considerable therapeutic challenge