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Entries in spiders (2)

Monday
May212012

Spider Phobics Hold Hairy Tarantula, Get Cured

Katherina Hauner(CHICAGO) -- B.D., a 34-year-old with a lifelong fear of spiders, found his phobia intensified after a trip to Australia where he encountered the Huntsman variety, a hairy tarantula that scuttles out from behind curtains and is notorious for entering cars and scurrying across the dashboard.

But today, after two hours of exposure therapy as part of a study at Northwestern University, B.D. finds spiders tame and amusing -- so much so that he allowed a hairy, Chilean rose tarantula named Florence to amble up his arm.

"It was like the ultimate extreme sport, a chance to face my fears in a very literal sense," B.D., an administrative assistant, wrote on a blog about his experience on his blog, "Room 101."

"It's been three years now, but I am still amazed whenever I react calmly and reasonably to their presence in my life," he wrote. "Just yesterday I helped a big green fellow off my desk, marveling that I didn't flee the room instead."

In 2009, B.D. was paid $100 to take part in a study at Northwestern University's Feinberg's School of Medicine, the first to document the immediate and long-term brain changes after exposure therapy. There, 12 terrified subjects were exposed to a variety of spiders -- first in photos, then in a terrarium and finally in the palm of their hands.

The study revealed that a single brief therapy session for adults with a lifelong fear of spiders -- or arachnophobia -- showed lasting changes to the brain's response to fear.

Arachnophobia is one of the most common specific phobias, and those who are afraid will go to great lengths to make sure they never see a spider. They may avoid hiking or camping or any situation where a spider might be present.

Specific phobias, which fall under anxiety disorders, affect about 7 percent of the population, according to the researchers. The most common include fear of blood, needles, snakes, flying and enclosed spaces.

But they say that their study may be applicable to all kinds of common phobias, as well as obsessive-compulsive disorder and post traumatic stress disorder.

"Before treatment, some of these participants wouldn't walk on grass for fear of spiders or would stay out of their home or dorm room for days if they thought a spider was present," said lead researcher Katherina Hauner, a post-doctoral fellow in neurology.

"But after a two or three-hour treatment, they were able to walk right up and touch or hold a tarantula. And they could still touch it after six months. They were thrilled by what they accomplished."

The study, which was published in the journal, Proceedings of the National Academy of Sciences, was the first to use functional MRIs to measure anxiety in the brain before and after exposure to the feared object.

Not only were patients less afraid after the two-hour therapy session, but they were phobia-free six months later.

The anxiety levels in their brain were measured at different intervals. When subjects experienced fear, certain parts of the brain, like the amygdala, insula, and cingulate cortex, lit up with activity on a functional MRI scan.

When the same study participants were asked to touch the tarantula six months later, "they walked right up to it and touched it," according to Hauner said.

Study participants had to meet the criteria for specific phobias as defined by the American Psychiatric Association's a Diagnostic and Statistical Manual of Mental Disorders.

"They had to be much more afraid of spiders than the average person," said Hauner. "And to meet the diagnostic criteria, it had to interfere with their life."

"Some wouldn't go home or stay in a dorm room for days if they thought a spider was there," she said. "One person avoiding traveling -- but after the study, they went on a trip."

Researchers used hierarchical steps to introduce patients to the feared object, first in photos of different spiders and then approaching a live one.

Copyright 2012 ABC News Radio

Wednesday
Jan262011

Afraid of Snakes? Scientists Explain Why

Photo Courtesy - Getty Images(NEW YORK) -- Fear of snakes, spiders and other creepy crawlers is so universal that most of us probably believe we must have been born with it. It's universal, so it must be innate.

Not necessarily, according to research at several major universities.

That work suggests that we learn which things can be harmful at a very young age -- even just a few months -- because we have an evolutionary bias that predisposes us to fear things that have posed a threat throughout human history.

"What we're suggesting is that we have these biases to detect things like snakes and spiders really quickly, and to associate them with things that are yucky or bad, like a fearful voice," developmental psychologist Vanessa LoBue of Rutgers University said in releasing the research.

LoBue's co-authors of the study, published in Current Directions in Psychological Science, are David H. Rakison of Carnegie Mellon University and Judy S. DeLoache of the University of Virginia.

The research is based on experiments with infants and very young children to see if they automatically know something can be harmful, like a snake, or if they have to learn it by observing fearful faces of adults, or associating a snake with something unpleasant, like a loud shriek.

They found repeatedly that babies don't recognize something as potentially harmful until they are conditioned to do so by something in their environment, and even then they may not show actual fear for a while.

"We propose that humans have a perceptual bias for the rapid detection of evolutionarily relevant threats and a bias for rapid association of these threats with fear," the researchers conclude in their paper.

But we weren't born with it, and in some cases female babies reacted differently from male babies, possibly explaining why some little boys seem fearless of snakes and spiders and things that go bump in the night, but most little girls scream at the mere sight of a snake.

In his part of the research, Carnegie Mellon's Rakison studied 11-month-old infants to see if an image of a snake, for example, alongside a human face showing either happiness or fear, would cause them to recognize that a snake is either harmless or dangerous.

It worked for the girls, but not the boys.

He found that "11-month old girls -- but not boys of the same age -- associated recurrent threats with fearful faces," according to the study. Interestingly, when the babies were shown flowers or other non-threatening images along with faces showing either fear or happiness, it made no difference.

That suggests the presence of a bias to recognize that snakes may be threatening, but not flowers. 

Copyright 2011 ABC News Radio







ABC News Radio