As any parent will tell you, teenagers can be emotional, display irrational behaviour and make bad choices.
Now, scientists believe they have found out why.
They say a teenage brain really does work differently to an adults.
The Duke University team say making a snap decision usually means following your initial reaction — going with your gut.
That intuitive feeling sprouts from the limbic system, the evolutionarily older and simpler part of the brain that affects emotion, behaviour and motivation, they say.
However, during adolescence, the limbic system connects and communicates with the rest of the brain differently than it does during adulthood, leaving many adolescents vulnerable to riskier behaviours, the team found.
‘We know adolescence is a time of profound social change. It’s also a profound time for risk-taking — a time period when peer influence is more important,’ said Kevin LaBar, a professor in the Duke Center for Cognitive Neuroscience.
‘This is when we start establishing independent relationships with adults, and some of those relationships are going to be influenced by how trustworthy those people are.
‘It’s important in these relationships to evaluate who you can and can’t trust.’
The new study, which appears in the March 2014 Social Cognitive and Affective Neuroscience, examines this capability in adolescent girls, ages 10 to 20.
The researchers found the teens were particularly sensitive to facial features linked with mistrust, which according to previous research, are faces with downward-turned mouths and furrowed eyebrows.
‘These heightened responses for untrustworthiness suggest that during this time, girls this age are particularly sensitive to the facial features they feel are untrustworthy,’ LaBar said.
‘We don’t know why. Maybe it’s a post-pubertal hormone change that brings on the heightened response, or maybe they’re more motivated to scan for social threats during this period.’
This study’s findings could help design prevention and treatment interventions that hone in on risky decision-making or help adolescents with mental illness rely more on themselves to make decisions.
