Spiders, heights, clowns, snakes, and flying are commonly feared by many around the world. Though there is no cure set in stone, people have dealt with their phobias using a variety of treatments such as exposure therapy, medication, or completely avoiding the source of the fear if possible.

But now, an effective cure may be on the horizon, according to researchers based at Advanced Telecommunications Research Institute International in Japan, and University of California in Los Angeles (UCLA).

The newly published study is based on experiments where the research team was able to reduce the fear participants had of animals such as snakes and spiders. The procedure involved directly manipulating the brain activity in the participants, while completely bypassing their conscious awareness. 

It used artificial intelligence similar to the computer algorithms that identify faces in pictures. Using conventional fMRI images, the researchers were identify unconscious spontaneous occurrences of mental images in the brain, like if a participant's brain was "unconsciously" thinking of a snake. By offering a small, monetary award to the participant every time this occurred, the brain started linking the snake with a positive feeling. The feared animal was eventually met with "reliable reductions in physiological fear responses."

"We knew it could work in principle. The challenge was to figure out how to read out the snake-related thoughts from the brain images in the clinic, with actual patients rather than normal participants in the laboratory," says lead author Dr. Vincent Taschereau-Dumouchel, a clinical psychologist by training.

He explained the complication with this method since if they were to "apply this procedure to patients, who are uncomfortable with seeing snakes in the first place, this becomes a problem," as they would not be able to proceed without knowing the brain patterns of a snake image.

So how was this problem solved? Professor Hakwan Lau, based at UCLA as well as the University of Hong Kong, explains that the brain activity could simply be inferred from another person and not necessarily the person with the phobia.

"Let's say you are afraid of snakes. To decode the patterns of your brain activity, you do not necessarily have to see snakes. I, as a surrogate of yours, can see snakes for you, as I'm not afraid of them. From there, we could computationally infer what should be your brain signature for snakes, based on mine, with an ingenious method devised by the Haxby lab at Dartmouth, called hyperalignment," Lau elaborated.

The researchers acknowledged that the method is still an experimental demonstration, double-blinded in nature where participants were not informed about the purpose of the experiment in order to maintain the unconscious nature of the procedure. They have expressed plans to test the method on actual phobic patients, which if successful, may inspire more effective treatments for similar psychiatric illnesses such as post-traumatic stress disorder.