Adolescence is a time of remarkable physiological and psychological change, and scientists are probing the innermost regions of the brain to explain why teens act the way they do. The brain continues to grow well into the 20s, and cognitive reasoning is developed to process more complex ideas and information. As adolescents become more mature, they develop new skills and seek more autonomy. While the social contexts in which today’s adolescents function differ from those of past generations, the factors they have in common are the influences of setting and environment on learning and behavior.
Spending quality time with children in a loving environment is the best indicator of how teens interact with others, according to Dr. Jay Giedd, neuroscientist at the National Institute of Mental Health. The brain is wired to connect with caregivers, whoever they may be. Changes that take place in the cerebellum -- back part of the brain -- account for mental aptitude and the ability to function well socially. The environment, relationships and social connections are the biggest markers of social development in adolescents, according to Ellen Galinsky, social scientist, as told in an interview with Frontline on the PBS website. In research using more than a thousand children, Galinsky found that teens actually want more interaction with parents, not less.
During childhood, the part of the brain -- called gray matter -- that controls impulses, decision making and judgment grows at a rapid pace and crests at age 11 or 12, just as children are entering puberty. Dr. Giedd likens it to a tree with roots and branches spreading in all directions. When the process is complete, the brain prunes the unused or unnecessary connections, and the ones left adapt to the environment. Researchers are focusing on understanding what is taking place during the buildup and pruning of gray matter. Dr. Giedd says brains have adapted over time to be able to handle skills, from learning to read to the ability to multi-task in today’s fast-paced era. The digital age has challenged the brain even more. Young people who have grown up during this period know nothing else, and the brain easily grasps associated concepts.
Physical and mental activity strengthens the brain connectors so those brain cells are not pruned or die off. Passive activities, such as watching television, do nothing to nourish the brain cells; therefore, they may not survive. The enhancement of the cerebellum occurs when teens engage in more physical activities rather than in passive ones. Because today’s youth are less and less physically active, scientists are pondering the effect on the development of the cerebellum. They are still unsure of the long-term effects of inactivity on the brain. Both the cerebellum and the frontal lobe ascribe to the “use it or lose it” tenet.
Scientists have found that there is a decline in proficiency relating to learning new and unfamiliar things during puberty. The reasons are not yet clear, but experiments carried out on mice by Sheryl Smith, professor of physiology and pharmacology at New York Downstate Medical Center, have revealed biochemical changes in mice as they performed a difficult task. She has not yet applied the experiment to humans. In addition, Robert McGivern, San Diego State psychologist, found, in a study of 300 adolescents, that it took them longer to perform a simple task and attributes this to the excess number of connectors in the brain. He thinks the decline may also be due to the lack of attention to routine learning in favor of more social interests.