[Paleopsych] NYT: What's the Lure of the Edge?

[Premise Checker]

What's the Lure of the Edge?
http://www.nytimes.com/2005/06/20/health/menshealth/20friedma.html

    By RICHARD A. FRIEDMAN, M.D.

    DURING a vacation last winter, I took a zip-line canopy tour of the
    Costa Rican rain forest. Strapped into a harness 100 feet above the
    jungle floor, I was flying through the air, with the toucans and
    parrots, attached to a steel cable strung between two platforms. I was
    having far too much fun to think that this could be dangerous. At
    first it was pretty thrilling, but by the 10th zip line I felt it was
    losing its charge.

    On the last and highest platform, a guy just in front of me began to
    hyperventilate. Being a psychiatrist, I realized he was having a panic
    attack. I got him to relax with some deep breathing and then asked him
    whether he had had this problem before. "Oh, yes," he said. "I thought
    this would be a way to conquer my fear of heights."

    Why was he terrified by what was beginning to bore me? We were both
    members of the sex that studies and more informal surveys indicate is
    more drawn to thrill seeking (for better or worse - more men than
    women have orbited the earth, while men are two to three more times
    likely to be pathological gamblers). But this man and I seemed to be
    on opposite ends of the thrill-seeking spectrum.

    On an individual level, the difference seems to be hard-wired in our
    brains, scientists have begun to discover. What is more surprising is
    that thrill seeking appears to be enjoyed not just by an elite - or,
    as some think, aberrant - bunch of people who put their lives at peril
    for a jolt of excitement.

    The focus of research on a relatively small, though dramatic, group of
    unsavory characters like psychopaths and drug addicts can give the
    impression that thrill is only for the mentally unbalanced. Far from
    it. Thrill seeking in one form or another is so widespread that it has
    practically become institutionalized in the culture. From reality TV
    shows like "Fear Factor," shot through with danger and risk, to the
    growing popularity of extreme sports, there is something to suit
    everyone's taste.

    The root of the thrill-seeking experience lies in an ancient neural
    circuit buried deep inside the brain that is intimately involved in
    pleasure, reward and novelty seeking. This system, which connects our
    thinking cortex with our more primitive limbic emotional center, runs
    on dopamine, a neurotransmitter. Many of life's greatest pleasures
    feel good because, in the end, they cause the release of dopamine from
    the brain's reward pathway. Sex, food and recreational drugs all flood
    the brain with dopamine - and so does thrill seeking.

    Like just about every other human attribute, there is great variation
    in individual taste for novelty and thrill seeking, much of it rooted
    in the brain. For example, Dr. Nora Volkow at the National Institute
    on Drug Abuse has shown that response to euphoria-producing drugs is
    related to the levels of brain dopamine receptors.

    In one experiment, she gave normal male controls intravenous Ritalin,
    which releases dopamine, and found that those who experienced the drug
    as pleasant had significantly fewer dopamine receptors than
    participants who reported unpleasant effects. Those with more dopamine
    receptors at baseline are probably less likely to abuse drugs or seek
    any thrill because their brains already have more dopamine activity to
    start with. In fact, these guys are likely to be thrill-averse, like
    that fellow I met on the zip line.

    For the chronically underaroused, a simple bike ride or jog in the
    park doesn't do the trick; it would take something more intense like
    diving 50 feet into a gorge or snorting cocaine to provide them with
    enough dopamine for them to feel excited.

    An entire industry has emerged in the last decade to satisfy such
    voracious appetites for thrills. Rich Hopkins, an inveterate surfer,
    stuntman and extreme sportsman, is president of ThrillSeekers
    Unlimited, a company he founded in 1992. Clients try anything from
    skydiving, bungee jumping and paragliding to zip-line or stunt
    driving. They will even give you the "fire burn," where you are set
    safely on fire, like a real stuntman. "When we started, we had around
    50 to 75 customers that first year," Mr. Hopkins said. "Now, we
    routinely take out several hundred people in just one adventure."

    Who are these thrill seekers? About 80 percent are men, Mr. Hopkins
    said. But the big surprise is that some of the largest clients are
    corporations and that many participants are men well into their 50's
    and 60's. "Instead of a golf holiday, they are sending their employees
    for an extreme sports adventure and they love it," Mr. Hopkins said.

    Charles Edwards has been chasing tornadoes in Oklahoma ever since he
    studied meteorology in college. "I've been obsessed with tornadoes for
    the last 15 years," he said. "Every storm is completely different, and
    you just get this adrenaline rush and try to get as close as possible
    to them. I've seen houses getting blown apart and cows tossed aside.
    Just awesome."

    Mr. Edwards was so hooked by the thrill of chasing storms that he
    created his own company, Cloud 9 Tours, to support his habit, as he
    called it. "We take people out during the tornado season here in
    Oklahoma, from April through August. These guys come back again and
    again."

    But what about thrill-averse guys? Can they learn to enjoy a little
    more excitement? If so, would thrilling activity itself change their
    neural circuitry to make them more like thrill lovers?

    Probably not, judging from studies of Dr. Jerome Kagan at Harvard, who
    has shown that certain temperamental traits you are born with are
    pretty stable. Using M.R.I. brain scanning, Dr. Carl Schwartz at
    Harvard recently found that these anxious adults showed greater
    responses in the amygdala, a brain region that processes fearful and
    threatening stimuli, to faces of strangers than to familiar faces. In
    other words, people who like novelty have biologically different
    brains than cautious folks, and no one knows if experience changes
    this.

    Of course, the surge of dopamine that thrill seekers search out can
    literally be addicting. The reason is that anything that activates our
    reward system, whether it's a natural reinforcer like sex, food or a
    thrilling act, is seen by the brain as something that should be
    repeated - over and over. And despite how smart we think we are, our
    brain can't really distinguish among the activating effects of drugs,
    thrill or useful behaviors. Even worse, for some people, drugs and
    thrill are more powerfully self-reinforcing than even food and sex. So
    the very design of our brain that promotes survival also makes us
    vulnerable.

    Alain Robert, a k a Spiderman, is known for climbing skyscrapers
    without special equipment or a safety net. He recently climbed the
    Taipei 101 Tower in Taiwan, which, standing at 1,670 feet, is the
    world's tallest building. "The euphoria when I reach the summit maybe
    lasts a few hours or days at the most, and then I have to have it
    again," he said. "I enjoy the risk and to be in control of my fear and
    have to do it again and again. I cannot stop climbing."

    Not all men get their thrills in such physically spectacular ways as
    Mr. Robert; some get it from their work.

    James Cramer, a founder of TheStreet

    .com and a financial commentator, used to manage a hedge fund. "I
    craved the risk," he said. "I would come to work and if by midday I
    hadn't made a serious bet, I'd be miserable. The bigger the bet, the
    better."

    "I got such energy and felt so alive," he added, "I was ecstatic on a
    daily basis."

    For some, though, there may be more to thrill than only a dopamine
    rush. "Guys like extreme sports not just because it's exciting, but
    because it makes them feel accomplished and more self-confident," Mr.
    Hopkins said.

    John Bardes, a freshman at Carleton College in Northfield, Minn., who
    enjoys scaling 50-foot walls, echoed this. "The wall is a genuine test
    of your ability and if your muscles can't make it, you fall. It's a
    way of finding your limits and seeing how far you can push yourself."

    Mr. Bardes, however, is not fearless. "At first I was nervous, and the
    higher I went the more anxious I became," he said. "But I got over
    that. Up there, I feel like I'm alone in my own world and it clears my
    head."

    Thrill has a dark side, too. In the sexual arena, it can literally be
    fatal. Men with a strong taste for sexual novelty in the form of
    multiple partners are at high risk of both getting and spreading
    H.I.V. and other sexually transmitted diseases as they move from one
    encounter to the next.

    But few forms of thrill are as insidiously destructive as gambling.

    Recently, scientists have peered into the brain while people are
    playing a game that simulates gambling. Dr. Hans Breiter at Harvard
    had subjects play a computer game of chance in which they either won
    or lost money, and monitored their brain activity. He found that the
    prospect of winning money activates the same dopamine reward pathway
    in the brain as recreational drugs like cocaine do. No wonder gambling
    is so compelling. This also helps explain why gamblers, like drug
    addicts, often seem helpless to resist an impulse that brings intense
    pleasure but can ruin their lives.

    Curiously, winning the prize is not what seems to make gambling so
    thrilling and addictive. Dr. David Zald at Vanderbilt University
    measured dopamine release in a group of subjects who played a computer
    game in two different conditions. In the first, subjects selected one
    of four cards and knew they might win a $1 reward, but didn't know
    when it might occur. In the second, subjects knew ahead that they were
    guaranteed to win $1 with every fourth card.

    Dr. Zald found a large increase in dopamine activity when winning was
    unpredictable, but not when the subjects knew what was coming. The
    implication is that gambling is powerfully addictive precisely because
    the outcome is uncertain.

    Believe it or not, thrill seeking is pretty much a modern phenomenon.
    Our hominid ancestors did not bungee jump or do any of the silly
    things that we do these days for thrill. Life back on the savannah was
    exciting enough on its own, with ferocious predators and an overall
    lack of amenities.

    Nowadays, where the basics like food or a sexual partner are a mouse
    click away, we don't really need our reward circuit for survival; we
    are free to use it just for pleasure. (To determine your risk comfort
    level, you can try a test adapted from the Zuckerman-Kuhlman
    Personality Questionnaire at [3]nytimes.com/menshealth.)

    With few exceptions, like 9/11, modern life has become so safe and
    controlled that you have to work at finding a little excitement. In
    fact, one might predict that as life becomes more predictable, riskier
    forms of excitement will emerge. Hang gliding off Mount Everest?
    Antarctic triathlon? There's no telling what's next.