The two periods of life when the brain grows most quickly are infancy and adolescence.  While during infancy, the brain’s growth is towards sensation and perception, during adolescence, the brain is growing towards using logic and abstract thought.  It does this by developing links with the prefrontal cortex. The prefrontal cortex is the area of the brain responsible for decision making and sentience.  This brain area also plays a large role in interpreting reality.  For teens, this area of the brain is largely underdeveloped.

The yellow area is the prefrontal cortex

The yellow area is the prefrontal cortex

Because of the underdeveloped nature of the prefrontal cortex, other areas of the brain take over.  Namely, the hypothalamus ends up playing a large role in emotional management and decision making.  This primative part of the brain, home of the fight or flight responses is what responds when teens are faced with emotionally-charged or challenging situations.  They are learning to use their more throughtful prefrontal cortexes, but they are not fully operational yet.  That is part of the reason why a teenager may go from calm to explosive quickly with a disproportionate trigger.*

The underdevelopment of the prefrontal cortex has also often been blamed for adolescent impulsivity.  Biologically, it is more difficult for teens to regulate some of their decisions.  However, a recent study put out by the Society for Research in Child Development found that some of the decisions teens make are more related to sensation seeking than a lack of self control or impulsivity.

One conclusion I come to from this study is the importance of having opportunities for teens to engage in “safe risk.”  Some possible opportunities that come to mind include: rock climbing, service projects in a different environment and wilderness camping.  Those activities in particular serve a dual purpose of not only using adolescent sensation seeking for positive experiences, but also building self esteem and self reliance.  What do you conclude from the role that sensation seeking plays in seemingly impulsive behaviors?

*Note: The underdeveloped nature of the prefrontal cortex does not justify violent or abusive behavior.  If you know a teen who consistantly demonstrates disproportationate and aggressive responses, please seek help from a professional.

Society for Research in Child Development (2009, February 6). Young Teens Really Are Shortsighted, But Don’t Blame Impulsivity. ScienceDaily. Retrieved February 7, 2009, from­ /releases/2009/02/090206081312.htm