[Editor’s note: MommaSaid’s Melanie Davis, of the Buzz on the Birds and the Bees, and Kathy Sena, of Boo-Boos, Germs & Pap Smears, are teaming up to tackle the news about this study on how earlier or later puberty can trigger aggression in boys.]
by Kathy Sena
Is your son way ahead of his friends when it comes to his voice getting deeper, his pants getting shorter and his face showing a bit of stubble?
Or is he at the other end of the spectrum — feeling left behind and wondering when he’ll hit puberty like many of his friends already have?
Puberty that arrives earlier or later in boys, compared with their buddies, can trigger chemicals related to antisocial behavior, say Penn State researchers. They add that their findings have important implications for parents with aggressive boys.
“Aggressive behavior can begin very early, even in pre-school, and might be related to poor impulse control, difficulties in the family or just overall general problem behavior,” says Elizabeth J. Susman, a professor of biobehavioral health at Penn State. “We wanted to find out if earlier or later timing of puberty in adolescents has any biological factors related to it.”
She and her colleagues looked at how the timing of puberty affects cortisol (a stress hormone) and salivary alpha amylase (an enzyme in saliva used as an indicator of stress). Their findings appear in the May issue of the medical journal Psychoneuroendocrinology. (OK, that’s a mouthful.)
The researchers used a child-behavior checklist to test 135 boys and girls ages 8 to 13 for signs of aggression, rule breaking, social and attention problems, defiance and conduct disorder. They also collected saliva samples before and after a stressful laboratory test, while pediatric nurses determined the stage of puberty for each child.
“We had the children tell a story and do a mental arithmetic test,” says Susman. “To evoke a stress response, the children were told that judges would evaluate the test results with those of other children.” Sounds like they did a pretty good job of simulating a typical school experience.
The researchers found that lower levels of alpha amylase in boys who experienced earlier maturity, and higher levels of cortisol in boys who experienced later maturity, are both related to antisocial behavior.
As parents, it’s important to be sensitive to picking up signs of earlier or later puberty in our kids, Susman says. “Parents and healthcare providers should be aware of how puberty can be stressful — behaviorally and biologically — on the kids.”
Did they find similar results in girls? No. And why the findings are statistically significant for boys and not girls isn’t clear.
The researchers’ best guess: “At puberty, boys produce a lot of testosterone, and testosterone is a stress hormone as well,” says Susman. “It may be that compared to girls, boys just have more biological hormone changes that may lead to antisocial behavior.”
Is all this something for parents to lose sleep over? Probably not. But it’s good to know the results of this research and to keep it, mentally at least, in your back pocket in case issues come up that warrant a chat with your child’s doctor.