Syncing exposure to fear triggers with a person's heartbeat improves phobia treatment, a new study shows.
In previous work, scientists at Brighton and Sussex Medical School (BSMS) in the United Kingdom demonstrated that the amount of fear that exposure to a potential threat can generate depends on the stage of the heart's pumping cycle with which it coincides.
They found that the emotional impact was greater when threat exposure coincided with heartbeats as opposed to occurring between them.
This finding motivated them to see if they could apply the effect to "influence the outcomes of computerized exposure therapy for spider phobia." The journal Psychosomatic Medicine has recently published this new research.
"Many of us," says senior study author Prof. Hugo D. Critchley, the chair of psychiatry at BSMS, "have phobias of one kind or another — it could be spiders, or clowns, or even types of food."
He goes on to explain that most treatments for phobia involve exposure to the specific fear trigger but notes that "this can take a long time."
Irrational, intense fear
A phobia is an irrational, intense fear that is vastly out of proportion to the actual danger or risk that the perceived threat poses.
Common examples include: a fear of spiders, dogs, or insects; a fear of heights, water, or storms; a fear of being in an elevator, enclosed, or on an airplane; and a fear of needles, injections, or surgical procedures.
The anxiety that the perceived threat generates can be so great as to disable the person. Just thinking about the feared situation or object can trigger severe symptoms, even though the person knows that their fear is irrational.
Estimates for the United States suggest that 12.5 percent of adults will have some kind of specific phobia during their lifetime.
Treatment for phobia typically takes a long time, and it usually involves gradually increasing exposure to triggers of the specific fear. One method that is gaining ground is computerized therapy, which it is possible to deliver over the Internet.
The recent study is a "proof-of-concept clinical trial" that demonstrates how computerized therapy for phobia could be even more effective if it were to sync trigger exposure with the individual's own heart rhythm.
Timing with heartbeat led to best results
Prof. Critchley and his team combined the computerized exposure with online monitoring of heart rhythm.
They assigned 53 otherwise healthy individuals with severe spider phobia to one of three computerized therapy groups. In all groups, the treatment involved exposure to images of spiders.
In the first group, the spider images appeared at the same time as the individuals' heartbeats, while the participants in the second group viewed them between heartbeats. In the third group, the images appeared at random with respect to the cardiac cycle.
The team assessed improvement by measuring changes in the participants' levels of anxiety, self-reported fear of spiders, and skin conductance.
All groups showed some improvement, as they all received exposure therapy in some form. However, the greatest improvement occurred in the group whose spider image exposures coincided with their heartbeats.
The improvement was particularly marked in individuals who were able to sense their heartbeat in their chests. The researchers suggest the possibility of using people's differences in this ability to personalize the therapy.
"You could say we're within a heartbeat of helping people beat their phobias."
Prof. Hugo D. Critchley