Frances E. Jensen, mother and neuroscientist from the University of Pennsylvania, began her own scientific study of the teen brain, when she found some of the behavior of her own teenage sons hard to understand. Parents often complain about life with teens and young adults,  They can be erratic, moody, unable to plan and often seem to give in to impulse rather than careful thinking.  But Jensen’s research explains much of what has baffled parents and she explains,  “We expect a little bit more out of adolescents than we should, given where their brains are.”   Here is what Jensen’s research can tell parents.

1.Teen brains do not finish developing until long after the teenage years. And while your teen or college student may look like and adult, Jensen says that her research shows that the brain may not be fully developed until a person is in his late 20s or even early 30s. The last part of the brain to fully develop is the frontal lobe. This is the part of the brain responsible for anticipating consequences, choosing between good and bad actions and inhibiting socially unacceptable behavior.

2. Teen Brains are not just younger adult brains.  Teen brains are not, as Jensen says, adult brains with fewer miles. The teenage years are an expansive time for the brain, full of creativity and learning. Because of synaptic plasticity, teens can learn faster and absorb more information.  Memories formed in this time seem to last longer, something older people understand when they think back on their youth.

3. Teens are more prone to addiction because it is essentially another form of learning.  In addiction there is repeated exposure to stimuli and reward and the brain learns a pattern.

 “It is important for adolescents to know that they can get addicted faster. ...Effects of substance abuse are more permanent on the teen brain. They have more deleterious effects and can be more toxic to the teen than in the adult. This is still a very imprintable, impressionable period of brain development,” Jensen explains.  Addictions gained during the teen and young adult years can be very hard to break. Those who begin smoking cigarettes during these years have a particularly hard time quitting. 

4. Jensen urges parents to stay closely connected to their teens and young adults remembering that they are not fully mature.  Even if their grown children are off at college or living on their own she urges parents to keep an eye on any psychological problems that might arise in these years. Some mental illness does not appear until young adulthood, often during the college years.  Depressions, bipolar disorder and schizophrenia all appear at the onset of adulthood when prefrontal and frontal lobes are fully “connected” and the brain has matured.

5. IQ is not set in childhood and can rise or fall during the teen years and be altered by the use of marijuana. Many believed that IQ, the commonly used measure of intelligence was fixed and that tests done in childhood and later in life would yield the same results. This turns out not to be true, Jensen explains, “We don’t quite know what specifically can make an IQ go up or down, but one thing that we know does make IQs go down is certainly exposure to certain drugs, for instance chronic pot smoking;  the more you smoke, the lower your IQ will be between that time window."

For more information see: The Teenage Brain: A Neuroscientist's Survival Guide to Raising Adolescents and Young Adults by Frances E. Jensen and Amy Ellis Nutt