TUESDAY, May 22 (HealthDay News) -- Fear of spiders, a type of anxiety disorder, may be treatable in a single therapy session, according to a small new study.
People with a lifelong spider phobia were able to touch or hold a tarantula after a two- or three-hour therapy session, and the effectiveness of the therapy continued for at least six months, the Northwestern University researchers reported.
The lasting changes in the brain's response to fear after short-term therapy seen in this study offer new directions for treating other phobias and anxiety disorders, the researchers said.
"Before treatment, some of these participants wouldn't walk on grass for fear of spiders or would stay out of their home ... for days if they thought a spider was present," lead author Katherina Hauner, a postdoctoral fellow in neurology, said in a university news release.
"But after a two- or three-hour treatment, they were able to walk right up and touch or hold a tarantula," she said. "And they could still touch it [six months later]. They were thrilled by what they accomplished."
Functional MRI brain scans revealed that the regions of the brain associated with fear response lit up with activity when the 12 adult participants simply looked at photos of spiders.
The participants were then asked to gradually approach a tarantula in a terrarium but, on average, could get no closer than 10 feet.
As part of the therapy, the participants were taught about tarantulas and learned that their terror-causing beliefs about them were not true.
"They thought the tarantula might be capable of jumping out of the cage and onto them," Hauner said. "Some thought the tarantula was capable of planning something evil to purposefully hurt them. I would teach them the tarantula is fragile and more interested in trying to hide herself."
The participants learned to approach the tarantula in slow steps until they could touch the outside of the terrarium. They progressed to touching the tarantula with a paintbrush and a glove, and eventually to petting it or holding it with their bare hands.
Following therapy, brain scans showed that the participants had much lower levels of activity in the fear-response regions of the brain when they looked at photos of spiders. This reduced activity was still seen six months after therapy.
The study was published May 21 in the journal Proceedings of the National Academy of Sciences.
Fear of spiders is considered a specific phobia, a type of anxiety disorder affecting about 7 percent of the population, the news release noted.
The American Psychiatric Association has more about phobias.
-- Robert Preidt
SOURCE: Northwestern University, news release, May 24, 2012
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