For years adolescent mood swings have been blamed on raging hormones. The once happy cooperative children turn into monsters as they enter their teen years. Reckless driving, and drug use are among the greatest fears of parents. Scientists are now finding raging hormones are not necessarily the reason for these changes.

Around the age of 11, the brain undergoes major reorganization in the region that controls things like social behavior and impulse control. Neuroscientists have found this to be true in the last few years, and this discovery led them to see adolescence as a period when the brain is vulnerable to traumatic experiences.

Scientists have found that the adolescent brain is actually different and it is still growing. Until recently it was thought that the brain stopped growing by the time a child entered nursery school.

New brain imaging technology has such as MRI and PET scans have detected brain growth throughout childhood and adolescence. Because their brains are not matured, teens do not handle social urges and stress the way an adult would. That may explain why kids are so prone to reckless and unhealthy behavior.

Recently, in another study, researchers presented a series of time lapsed images depicting brain growth of children for ages 3 to 15. It showed an intertwining of nerve cells budding in the part of the brain above the eyes, then during a period when about half of the new fibers are trimmed away to create an efficient network of circuits.

This happens in the part of the brain known as the prefrontal cortex, which is responsible for functions such as goal setting, prioritizing, organization, planning and impulse inhibition. Part of the reason teens are not good at risk taking is because their brain isn’t fully developed.

Accidents are the leading cause of death among adolescence; teens are more likely to become victims of crime than any other age group. The majority of alcoholics and smokers get started during their teens, and a quarter of all people with HIV contract it before the age of 21.

Most of the research on brain development has been done on animals. Adolescent rats show more interest than adults do when strange objects are put in their cages. They explore more and jump from one activity to another, not able to focus their attention on any one activity for an extended period.

Part II to follow.