Less Exposure May Be More for Overcoming Phobias

Megan Brooks

February 16, 2017

When it comes to overcoming phobias, less vs more exposure to the object of fear may be more effective.

In a study of spider-phobic persons, researchers found that very brief exposure to a masked picture of a spider without conscious awareness was more effective and less stressful than longer conscious exposure.

"Counterintuitively, our study showed that the brain is better able to process feared stimuli when they are presented without conscious awareness," Paul Siegel, PhD, associate professor of psychology, Purchase College of the State University of New York, in Harrison, said in a news release. "Our findings suggest that phobic people may be better prepared to face their fears if at first they are not consciously aware that they've faced them."

The study was published online February 6 in Human Brain Mapping.

Participants included 21 spider-phobic persons and 21 nonphobic persons who served as controls. During functional MRI, participants experienced three scenarios: very brief exposure to masked images of spiders (severely limited awareness); exposure to clearly visible images of spiders (full awareness); and masked images of flowers (control).

Very brief exposure was accomplished through a technique called backward masking, in which a target phobic image is shown very briefly, immediately after which a nontarget image, or "mask," is shown. The mask prevents recognition of the target.

In the spider-phobic persons, very brief exposure to masked spider images strongly activated areas of the brain that support fear processing without causing the person to experience fear consciously, the researchers note.

Clearly visible exposure to the spider images, in contrast, deactivated regions supporting fear regulation and caused phobic participants to experience fear.

Dr Siegel believes that very brief exposure therapy could be used to combat a range of phobias as well as anxiety disorders.

"We see very brief exposure eventually being used in the clinic," he told Medscape Medical News.

"Most people with anxiety disorders do not come for treatment, because it requires them to confront their fears, which is highly distressing. Because the technique reduces fear unconsciously, it does not cause people to experience distress. If very brief exposure were used as a preliminary treatment, it could get people who are refusing treatment more likely to confront their fears," he added.

The next step, he said, is to conduct a randomized trial of very brief exposure while participants undergo brain imaging.

"We will directly relate the effects of this technique on brain activity to its subsequent effects on phobic symptoms," Dr Siegel said.

The researchers also plan to use this approach with combat veterans suffering from US posttraumatic stress disorder (PTSD). The vast majority of veterans with PTSD do not seek treatment, because they are averse to confronting traumatic memories, Dr Siegel said.

"This technique of very brief exposure may be particularly attractive to combat veterans because it does not cause distress and is a treatment that targets the brain rather than the mind, which will likely reduce their stigma concerns about seeking mental care," he noted.

Reached for comment, Cyrus Raji, MD, PhD, clinical fellow, Department of Radiology, University of California, San Francisco, said the study is "interesting" and noted that "understanding how the brain processes different types of fearful stimuli is an important step to developing better treatments for various phobias."

Funding for the study was provided by the National Institute of Mental Health, the American Psychoanalytic Association, the Society for Neuropsychoanalysis, the International Psychoanalytic Association and Purchase College. The authors have disclosed no relevant financial relationships.

Hum Brain Mapp. Published online February 6, 2017. Full text


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: