Teen brain responds differently to drugs than adult

New research released today shows teenagers respond differently to drugs than adults and explores the long-lasting effects of drug use on brain development. One study shows people who start using drugs at a young age have greater cognitive shortfalls, including mental flexibility. Animal studies also suggest adolescents are more susceptible to lower doses of cocaine, are willing to work more for a cocaine "fix" than adults, and are at risk of developing compromised stress responses. The research findings were presented at Neuroscience 2010, the Society for Neuroscience's annual meeting and the world's largest source of emerging news and brain science and health.

Teens' brains are only about 80 percent developed and are not complete until they reach their 20s or 30s. More than 4,300 U.S. teens try an illicit drug for the first time each day. Today's findings provide more clues to the unique effects of drug use at this time of life, and the potential impacts on brain chemistry into adulthood.

Research released today shows that:

• Animal research shows adolescents are more susceptible to lower doses of cocaine and work harder for it than adults (Michela Marinelli, PhD, abstract 574.18, see attached summary).

• Amphetamine abuse during adolescence permanently alters brain cells involved in memory and decision-making. This animal finding suggests abnormal brain responses in adults may result from drug abuse at a time when the brain is still developing (Joshua Gulley, PhD, abstract 576.6, see attached summary).
• Binge drinking during adolescence alters the stress response in rats as adults. Problems regulating stress are associated with behavioral and mood disorders (Toni Pak, PhD, abstract 792.20, see attached summary).

• People who start using marijuana at a young age have greater cognitive shortfalls. Researchers also found that the more marijuana a person used corresponded to greater difficulties in focus and attention (Staci Ann Gruber, PhD, abstract 165.9, see attached summary).

"As parents and neuroscientists, we desperately need to better understand how drug exposure during teen years influences brain development. With the help of further research, scientists and clinicians can lay a foundation for education, intervention, and treatment," said press conference moderator Frances Jensen, MD, of the Children's Hospital in Boston, and an expert on brain developmental stages and injury.