If you are the parent of teenager, you are likely to utter the following phrase numerous times during your child's adolescence -- "What were you thinking?" In fact, beginning around 1985, researchers began to discover that the teenage brain is different than the adult brain, which might account for adolescent behavior. Because the teen brain is still developing, it literally lacks the maturity of an adult brain. So impulsive, egocentric and risky behavior, hallmarks of the teen years, might be perfectly understandable after all.
Previous Theory
Until the last decade of the 20th century, scientists thought that the brain was fully developed by about the age of 10. As Harvard neurologist Frances Jensen explained to NPR, researchers believed "a teenage brain is just an adult brain with fewer miles on it." According to the National Institute of Mental Health, researchers led by Dr. Arthur Toga at UCLA used MRI imaging on the brains of children and teen to show that the teenage brain undergoes dynamic changes. Although research on the teen brain is still in its infancy, scientists believe the changes in the adolescence brain explain some aspects of teen behavior.
Current Research
As of publication date, research shows that the frontal lobes, also referred to as the prefrontal cortex, of teenagers are not fully connected. As a result, the connection with the rest of the brain operates more slowly than the brain of a person in their 20s. This is significant because the frontal lobes control reasoned behavior. It often is referred to as the CEO of the brain, modulating impulses and mood to an extent that the frontal lobes have been dubbed "the area of sober second thought." Toga's research team at UCLA believe a lack or myelin, also referred to as white matter, which coats brain nerves like insulation on electric wires, prevents the frontal lobes from communicating easily with the rest of the brain. The complete development of the frontal lobes does not occur until a person is in his 20s. In addition, the growth and pruning of gray matter also is occurring during the teen years..
Consequences
The teen brain not only lacks coordination, it is excitable. Teen brain chemistry is geared to taking in stimuli from everywhere in order to aid learning. By combining excitability with a shortage of impulse control, teens are wired for risky behavior and also wired to be more susceptible to addiction of all types. Teen perceptions of other people and the emotional reactions triggered in their brains are not as mature as adults either.
Considerations
Research by Dr. Jay Giedd at the National Institute of Mental Health shows that the growth and pruning of gray matter during adolescence is a critical time. Giedd told "Frontline" that the teen years are a "use it or lose it" time. "If a teen is doing music or sports or academics, those are the cells and connections that will be hardwired. If they're lying on the couch or playing video games or MTV, those are the cells and connections that are going to survive." If parents are aware of the brain changes their teens are coping with, they might be more understanding and more effective in helping steer them through the raging rapids of adolescence.
