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It's commonly assumed that testosterone, that stereotypically male hormone, is intimately tied to violence. The evidence is all around us: weight lifters who overdose on anabolic steroids experience "roid rage," and castration—the removal of the source of testosterone—has been a staple of animal husbandry for centuries.
"[Historically,] researchers expected an increase in testosterone levels to inevitably lead to more aggression, and this didn't reliably occur," says Frank McAndrew, a professor of psychology at Knox College in Galesburg, Ill. Indeed, the latest research about testosterone and aggression indicates that there's only a weak connection between the two. And when aggression is more narrowly defined as simple physical violence, the connection all but disappears.
One psychologist, James Dabbs of Georgia State University in Atlanta, made a career out of conducting studies connecting testosterone to every kind of lifestyle imaginable. In his book Heroes, Rogues and Lovers, he noted that athletes, actors, blue-collar workers and con men tend to have higher levels of testosterone than clerks, intellectuals and administrators.
What Dabbs didn't address was whether this correlation was the cause or an effect of the environment these men found themselves in. Which is to say, are high-testosterone males more likely to become violent criminals, or does being a violent criminal raise a man's level of testosterone?
No one really knows the answer, but a growing body of evidence suggests that testosterone is as much the result of violence as its cause. Indeed, both winning a sporting match and beating an opponent at chess can boost testosterone levels. (On the other hand, losing a sporting match, growing old and becoming obese all reduce levels of testosterone.)
Changes in testosterone levels in response to challenges can be further shaped by our expectations. In one experiment that put a biological spin on the red state–blue state divide, researchers at the University of Michigan at Ann Arbor had a volunteer "accidentally" bump into and then insult men who were raised either in the North or the South. The researchers hypothesized that Southerners come from a "culture of honor" in which aggressive responses to insults are culturally appropriate, and the results of their experiment bolstered that notion: Not only were Southerners more likely than their northern counterparts to respond with aggression, but their levels of testosterone also rose as a result. The Northerners, in contrast, were much less likely to experience an increase in testosterone
Arguably, the weak correlation between testosterone and violence gives us reason to be optimistic about the human race: Whereas other animals battle over mates as a direct result of their seasonal fluctuations in testosterone and other hormones, humans have discovered other ways to establish pecking orders. Which isn't to say that we can't rapidly adapt to the modern-day manifestations of our violent past: McAndrews's work demonstrated that one surefire way to raise a man's testosterone level is to allow him to handle a gun.
For the full read see
http://www.sciam.com/article.cfm?articleID=7DE01F25-E7F2-99DF-30D2199FCD555450&pageNumber=2&catID=9
"[Historically,] researchers expected an increase in testosterone levels to inevitably lead to more aggression, and this didn't reliably occur," says Frank McAndrew, a professor of psychology at Knox College in Galesburg, Ill. Indeed, the latest research about testosterone and aggression indicates that there's only a weak connection between the two. And when aggression is more narrowly defined as simple physical violence, the connection all but disappears.
One psychologist, James Dabbs of Georgia State University in Atlanta, made a career out of conducting studies connecting testosterone to every kind of lifestyle imaginable. In his book Heroes, Rogues and Lovers, he noted that athletes, actors, blue-collar workers and con men tend to have higher levels of testosterone than clerks, intellectuals and administrators.
What Dabbs didn't address was whether this correlation was the cause or an effect of the environment these men found themselves in. Which is to say, are high-testosterone males more likely to become violent criminals, or does being a violent criminal raise a man's level of testosterone?
No one really knows the answer, but a growing body of evidence suggests that testosterone is as much the result of violence as its cause. Indeed, both winning a sporting match and beating an opponent at chess can boost testosterone levels. (On the other hand, losing a sporting match, growing old and becoming obese all reduce levels of testosterone.)
Changes in testosterone levels in response to challenges can be further shaped by our expectations. In one experiment that put a biological spin on the red state–blue state divide, researchers at the University of Michigan at Ann Arbor had a volunteer "accidentally" bump into and then insult men who were raised either in the North or the South. The researchers hypothesized that Southerners come from a "culture of honor" in which aggressive responses to insults are culturally appropriate, and the results of their experiment bolstered that notion: Not only were Southerners more likely than their northern counterparts to respond with aggression, but their levels of testosterone also rose as a result. The Northerners, in contrast, were much less likely to experience an increase in testosterone
Arguably, the weak correlation between testosterone and violence gives us reason to be optimistic about the human race: Whereas other animals battle over mates as a direct result of their seasonal fluctuations in testosterone and other hormones, humans have discovered other ways to establish pecking orders. Which isn't to say that we can't rapidly adapt to the modern-day manifestations of our violent past: McAndrews's work demonstrated that one surefire way to raise a man's testosterone level is to allow him to handle a gun.
For the full read see
http://www.sciam.com/article.cfm?articleID=7DE01F25-E7F2-99DF-30D2199FCD555450&pageNumber=2&catID=9
