Posted on January 25, 2012

The teen years are not easy years. New schools, new friends, more difficult homework, puberty, growth spurts, voice changes, acne, and the joy and despair that come along with girlfriends/boyfriends are enough concerns to occupy a teenager’s brain. They are too young to have complete independence but too old to be treated like a little child.

This is also the age when most young adults will have their first experience in relation to drugs or alcohol. They might see friends using substances and decide to engage or not engage. It is a challenging time of making the best decisions they can for their mind and body.

Couple this with the fact that researchers have found that a teen’s decision-making part of the brain may be compromised once they begin using these drugs. The part of their young brains associated with rewards makes them more susceptible to forming an addiction than it does an adult.

Professor of neuroscience in Pitt University’s Kenneth P. Dietrich School of Arts and Sciences, Bita Moghaddam, led the study that was published in the Proceedings of the National Academy of Sciences. She was aided by coauthor David Sturman, a MD/PhD student in Pitt’s Medical Scientist Training Program.

Moghaddam and Sturman studied brain activity related to reward, motivation, forming habits, and decision-making in adult and adolescent rats. Using a method named "behavioral clamping", the researchers implanted electrodes into the brains of both adolescent and adult and rats to study whether neuron activity would cause the subjects to process identical behavior differently.

When anticipating a reward, adolescent rats had increased activity in a part of the brain called the dorsal striatum (DS). The DS in the adult rats was not increased. This distinction between adolescent and adult brain reactions is crucial in the different ways adults and youth may react to addiction because of the significance of the role of the DS. The DS is an area associated with forming habits, making decisions, and motivated learning.

Researchers reported that adults and adolescents had similar brain reactions in the nucleus accumbens, the part of the brain most often associated with reward and motivation. Moghaddam is anxious to continue research on how adolescent brains are motivated by rewards, form decisions, and influence the formation of habits.

Moghaddam is concerned about the implications from Pitt’s findings. If adolescents’ brains are more sensitive to reward anticipation than in adults, then this anticipation can directly affect the part of the brain responsible for making decisions and forming habits.

Moghaddam stresses that more research needs to be done to help adolescents avoid addiction to stimulants. His team plans to continue their research and hopes to develop prevention strategies for young adults based on their studies.