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The Teen Brain

The teen years are a time of great physical growth and body changes. Scientists have found that the teen brain is also developing and changing and that it is different from an adult brain.


Changing and Maturing

The greatest changes occur between puberty and early adulthood in the parts of the brain responsible for self-control, judgement, emotions and organization. This may help to explain certain teenage behaviours that adults find confusing such as: risk-taking, emotional outbursts and poor decision-making.1 2 3

The Frontal Cortex

The frontal cortex goes through a sudden growth spurt at about age 10-11. This part of the brain is the last part to mature at about age 25. The frontal cortex is responsible for:

  • Helping a person to think clearly
  • Organizing
  • Decision-making
  • Memorizing
  • Controlling impulses
  • Controlling emotions
  • Judegment

Image of a teen brain


What does it mean?

  • Teens don’t always think about the consequences of their behaviour. They may make poor choices. This may lead to risk-taking with cars, drugs, alcohol and sex. Help them to think about different situations and problem-solve ahead of time1
  • Teens may act younger then they look. They may not understand and handle information the same way adults do.  Even if you think you have explained something clearly, teens may still see the situation quite differently. Ask them what they think, how they see the situation, and involve them in a creative decision making

Amygdala: The ‘emotional centre’ of the brain. This part of the brain controls mood and emotions. It's very active in the teen years.

What does it mean for parents?

  • Teens are still learning to understand facial and body language and emotions.  They may over-react to situations or become easily upset. Think about their point of view, but calmly explain in other words what you mean.  Don’t take their response personally2 3
  • There are differences between boys and girls. Research shows that females are usually more calm and in touch with their emotional responses than males. Be aware of the differences between boys and girls. Help boys to understand and think about their emotions and feelings 2 3

More information for parents and teens:

  • The brain is made up of many parts and has different kinds of cells and tissue that are connected together. As the brain matures and develops, the connections in the brain that get used a lot will get stronger. If they are not used, they will die – a process called “pruning”.  This is the “use it or lose it” principle 2 3 5
  • The “pruning” process means that teens can control, to some extent, how their brains will develop!  Kids who “exercise “ their brains by learning new skills, understanding new, complex ideas and controlling their urges are helping their brains to develop and mature in a way that will help them for the rest of their lives 2 3 5
  • Since the teen years are a time for new experiences, challenges and opportunities, teens should be encouraged and supported to try new activities like sports or music, get involved in their community or join a club. This will help to “wire” their brains for these activities and these brain connections will become stronger 2 3 5
  • Research has shown that alcohol affects teens differently than adults. This is because the teen brain is still changing.  Learning and memory can be impaired and teens that use alcohol a lot can suffer long-term problems even weeks after the drinking stops1
  • Marijuana use during adolescence is associated with reduced brain functioning including lower performance on thinking tasks, poorer attention, decreased verbal memory and planning ability 4
Date of creation: February 27, 2013
Last modified on: August 28, 2014


1The Public Broadcasting System. Retrieved from
2Alcohol and the Adolescent Brain, Aaron M White PhD, Duke University Medical Centre.
3Teenage Brain: A work in progress, National Institute of Mental Health. Retrieved from
4The Teen Brain, Hard at Work, No, really. Leslie Sabbagh. Scientific American Mind, Aug/Sept 2006. Retrieved from
5University of Cincinnati (2008, October 15). Marijuana Use Takes Toll on Adolescent Brain Function, Research Finds. Science Daily. Retrieved from