Tuesday, March 8, 2005
The Guardian has an interesting article on puberty and the role of hormones. According to recent research, you cannot blame all the woes of your teenage years on hormones - it is much more complicated and involves a number of environmental as well (no real surprise there). The article is interesting and attempts to explain why teenagers engage in some bizarre and dangerous behaviors. The article states,
Teenagers get a rush from intensity, excitement and arousal. Loud music, big dippers, horror movies? That's where you'll find teenagers. In some teens this thrill-seeking and quest for novelty is subtle and easily managed. In others, the reaction is more severe and can become out of control. This is reflected in the statistics for teenager deaths, three quarters of which result from accident or misadventure.
It is tempting - indeed it has always been assumed - that such behaviours are entirely hormone-driven. After all, aren't teenagers hormones on wheels? From all that I have said so far, it seems logical. But links between hormone levels and poor behaviour in teenagers are either weak, or non-existent.
Nevertheless, if the number one risk factor for homicide is maleness (as it is) and the second is youth, and given that boys have loads of testosterone, and girls don't (or certainly not nearly as much), surely this must put testosterone in the dock as the cause of aggressive adolescent behaviour?
Actually not. First, there is no consistent relationship between normal circulating testosterone levels and violence in teenagers. In fact, there is a rather better correlation between high testosterone levels and levels of popularity and respect from peers. One hypothesis is that teenage boys pick up cues from the environment and use them to determine "normal" behaviour. This is illustrated by recent work from the MRC unit at the Institute of Psychiatry which shows that it is not testosterone levels that determine your waywardness as a teenager, but basically, the people you hang with. Keep the company of bad boys, and you will take your behaviour cue from them. Hang out with sober sorts and your behaviour will be like theirs. As we all remember, being split up from your best mate is a peril of adolescence. "They're a bad influence on you" is the general gist of parental or teacher wisdom on this one. Oh dear. The ignominy of the Institute of Psychiatry proving Miss Mansergh, year nine form teacher, right.
Deprivation may be a more important determinant of teenage violence. The theory - and there is a wealth of literature on this subject - is that if low-status males are to avoid the road to genetic nothingness (the words of neuroscientist Steven Pinker), they may have to adopt aggressive, high-risk strategies. If you've got nothing, you have nothing to lose through your behaviour. Certainly, in humans, both violence and risk-taking behaviour show a pronounced social gradient, being least in the highest social classes and most in the lowest ones. This is surely not what you would expect if testosterone were the only driver of violence.
Such research may have a positive impact on rehabilitation and re-direction strategies for youthful offenders. It should be interesting to follow the development of such findings. [bm]