Pubdate: Fri, 31 May 2002 Source: Wall Street Journal (US) Section: Science Journal Copyright: 2002 Dow Jones & Company, Inc. Contact: http://www.wsj.com/ Details: http://www.mapinc.org/media/487 Author: Sharon Begley WHAT MAKES THRILL SEEKERS TICK? Researchers Go Along For The Ride The roller coaster that plunges 98 meters. The log flume that leaves you staggering. The free-fall ride that separates you from your stomach. Some people love them. Some people would rather be boiled in the oil over at the Belgian waffle stand. With summer approaching, amusement parks are bracing for a flood of visitors, and visitors are bracing for the flood of adrenaline lost through thrill rides. Meanwhile, a cottage industry of psychologists, psychiatrists and even geneticists has started to work in pursuit of an explanation for why some people are sensation-seekers and others sensation-duckers. Who will ride the Millennium Force and who will hide out at the Sno-cone concession isn't a burning research question. But it sheds light on important, related ones -- such as who will drive 150 kilometers per hour, try heroin or play "chicken" on train tracks. "There is a common temperament that underlies the attraction to many kinds of risky behavior," says Marvin Zuckerman, a professor of clinical psychology at the University of Delaware who has studied sensation-seeking for 40 years. "Sensation-seekers tend to drive recklessly, to do drugs and drink. They are drawn to people who are exciting but not too reliable. They typically have many unstable relationships with lots of sexual partners. In every aspect of their lives, they're looking for the latest thing." Early on, explanations of the innocuous, roller-coaster sort of sensation-seeking focused on "vicarious fear." The idea is that the mind knows that making hairpin turns in a little car 60 meters up is actually less dangerous than driving (0.61 deaths per 100 million passenger miles in roller-coasters compared with 0.91 in automobiles, say the latest U.S. statistics). "So we can master that fear," explains Dr. Zuckerman. "And we take pleasure in mastering it." But clearly something more is going on in people who truly dare death, as in that game of railroad chicken. Not to put too fine a point on it, but what the heck is wrong with these people's brains? When in doubt, look to testosterone poisoning. "It had long been assumed that high testosterone levels are associated with sensation-seeking," says David Quadagno, a psychology professor at Florida State University. After all, more men than women drive fast and scale K2. But when his research team recently measured testosterone in men and women, and then checked the levels against answers to questions such as, "would you like to jump out of an airplane (with or without a parachute)?," they got a surprise. Men who copped to preferring a nice Bronte novel had testosterone levels no lower than those who opted for more adventure. "Testosterone levels are not associated with sensation-seeking in either sex," Dr. Quadagno says. Another culprit, the stress hormone cortisol, tells a different story. "Low cortisol levels were associated with sensation-seeking in men," Dr. Quadagno says. A low-cortisol man, he suspects, isn't stressed by the same things as other people. He is therefore willing and able to "up the ante and look for excitement." Are low-cortisol guys born or made? That is a mystery, but genes almost surely play a role. In 1996, geneticists announced the discovery of a "novelty-seeking" gene. It codes for a receptor in the brain that acts as a molecular docking site for dopamine. This brain chemical can produce a rush of pleasure and its release seems to underlie addiction. In people hooked on thrills, empty dopamine receptors make them almost as edgy as a smoker with empty nicotine receptors. As with any addiction, the dopamine rush from, say, Disney's spinning teacup ride eventually wears off. "To stimulate the system, you have to do something more," Dr. Zuckerman says. "That's why sensation-seekers need riskier and riskier thrills to get the same kick." Psychologists who deal with problem kids say sensation-seeking is more ingrained than aggression or impulsiveness. "It's less malleable because it's a trait of temperament, which has a strong genetic basis," says Deborah Capaldi of the Oregon Social Learning Center. "You might affect the associated behavior, but you won't change the underlying temperament." Still, there are thrills and there are thrills. A sensation-seeker who also is persistent and optimistic might become a star options trader; one who is resentful and impulsive might turn to crime. Nature deals the hand -- how we play it is up to us. Me, I'll be at the Sno-cone stand. - --- MAP posted-by: Beth