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June 01, 2015

A Look Inside the Teen Brain

Sally Small Inada

The views expressed herein have not been approved by the House of Delegates or the Board of Governors of the American Bar Association, and accordingly, should not be construed as representing the policy of the American Bar Association.

Troubling teen behavior: excessive risk-taking, difficulty understanding consequences, lack of focus in school, and staying up very late. This could describe youth behavior in the juvenile justice, foster care or truancy systems—and it’s also typical teen behavior “tied to the very much still-evolving functioning, wiring, and capacity of the adolescent brain,” according to neurologist Frances E. Jensen, MD, author of The Teenage Brain: A Neuroscientist’s Survival Guide to Raising Adolescents and Young Adults. 

Jensen says new research shows brain connectivity “slowly moves from the back of the brain to the front. The very last places ‘to connect’ are the frontal lobes. In fact, the teen brain is only about 80 percent of the way to maturity. That 20 percent gap, where the wiring is thinnest …goes a long way toward explaining why teenagers behave in such puzzling ways—their mood swings, irritability, impulsivity, and explosiveness, inability to focus, to follow through… and their temptations to use drugs, alcohol and other risky behavior.”   

Jensen’s book is effective and authoritative because she speaks as a scientist, doctor, and parent who raised two teenage boys by herself. Lawyers, dependency judges, court and agency staffs will find the book an accessible, scientific users’ guide with chapters detailing: 

  • Taking Risks
  • Tobacco
  • Alcohol
  • Pot
  • Hard-Core Drugs
  • Stress
  • Mental Illness, and
  • The Digital Invasion of the 
  • Teenage Brain.

In the chapter “Crime and Punishment” Jensen discusses her “adventure in the intersecting worlds of juvenile justice and neuroscience,” as she worked with a Washington DC law firm on an amicus brief for the recent Supreme Court decision striking down “life without parole” sentences for juveniles in nonhomicide cases. The chapter also explores “the complexity of applying neuroscience to legal culpability.”

 Teens are notorious for staying up late and wanting to get up even later. Jensen cites some of the latest research on effects of lack of sleep:

Poor Sleep habits may even have a role in juvenile delinquency. The Journal of Youth and Adolescence reported in 2012 that teens who slept seven hours or fewer a night had a significantly higher rate of property crimes such as shop lifting, vandalism and breaking and entering than peers who had eight to ten hours of sleep a night. Those teens who slept five or fewer hours a night had significantly higher rates of violent crimes…

She then switches to what parents, guardians, or foster parents can do to help teens get the necessary sleep:

As for your teenagers, suggest they do nontech activities before bed and do the same activities at the same time every night, not only to avoid melatonin suppression from the artificial light of computers, iPads and smartphone screens but also to habituate the body to wind down at the same time every night. 

Jensen’s “Final Thoughts” offer useful advice to parents, professionals or anybody who interacts with teens regularly: 

  • “Be tolerant of your teens’ misadventures, but make sure you talk to them calmly about their mistakes.

  • Don’t be shocked when your teens do something stupid and then say they don’t know why. You know why, but explain that to them—how their prefrontal lobes haven’t quite come online yet. And remember, even the smartest, most obedient, meekest kids will do something stupid before ‘graduating’ from adolescence.

  • Communicate and relate: Emphasize the positive things in your teens’ lives and encourage them to try different activities and new ways of thinking about things. Reinforce that you are there for them when they need advice.”

The Teenage Brain: A Neuroscientist’s Survival Guide to Raising Adolescents and Young Adults, hardcover $27.99, paperback $11.90   


Sally Small Inada, MA, is communications/information design director at the ABA Center on Children and the Law, Washington, DC.