Teenagers. I’ve got two of them and yes, at any given moment they can exhibit the usual moods and actions we associate with teens; but when we look at all their biological influences, their ability to stay on track at all is quite admirable. We talk a lot about hormones and rapid growth. While these do influence teenage behaviour, the biggest contributor is the teenage brain.
It is true that hormones can contribute to the typical teenage behaviours we associate with adolescence. They don’t suddenly appear as the teen years begin but some hormones do increase dramatically at the onset of puberty and strongly influence growth, development, sleep patterns and emotions.
There is a lot more to the story though, the brain has a large part to play. Although human brains have completed most of their growing by the time they are six (more than 90%), much of the actual development of the human brain happens between the ages of 12 and 25.
Our brains develop from the back to the front, meaning that the prefrontal cortex is one of the last areas to fully develop. So while adults make good use of this area, teens do not. Which is unfortunate, as this part of the brain deals with decision making, future planning and impulse control.
The prefrontal cortex is slowly building up connections with other parts of the brain during adolescence, so the wiring is incomplete. When teens make decisions they are not guided so much by this, logical thinking area, but more by the emotional part of their brains. This explains why teenagers tend to act in the moment, without much thought to risks involved or long term outcome.
Studies have also show that teens are less likely to correctly identify emotions in others. Adults rely a lot on the prefrontal cortex when reading the emotions on a person’s face. Teens get it wrong more often when relying on other parts of their brains.
While the prefrontal cortex is slowly developing, an area in the teenage brain, referred to as the limbic system, is already well developed. This area plays a role in emotional control, memory and the gratification process. It is little wonder, therefore, than teenagers are more influenced by emotion than logic in the decision making mechanism, their brains are literally wired that way.
The amygdala is part of the limbic system and it is known for its rapid responses to outer stimuli, controlling what is called the fight-or-flight process. It has a reputation for causing a reaction before the more conscious, thinking parts of the brain can register what’s going on. The amygdala also controls our emotional state and our social connections. It is thought to be influenced by the fluctuating hormones associated with puberty so it is no wonder really that teens can have such strong mood swings and emotional responses.
The teenage brain is also more attuned to the reward centre of the brain, the nucleus accumbens. With the right stimulus this part of the brain releases dopamine, explaining why teens are so reward driven.
With all this information, the teenage brain is an impressive organ, with its rapid development, constant pruning and rewiring and a very strong ability to learn. The real admiration has to go to the teens themselves that need to steer and control this driving force while under the influence of strong emotions and reward systems.