As children become teenagers, their brains grow and change. These changes affect their thinking and behaviour. When you understand how, you can better help your child build a healthy teenage brain.

Scientists once thought that brain development stopped after the first few years of life. Now we know that it keeps going well into adulthood.
Children’s brains have a massive growth spurt when they’re very young. By the time they’re six, their brains are already about 90-95% of adult size. But the brain still needs a lot of remodelling before it can function as an adult brain.
This brain remodelling happens intensively during adolescence, continuing into your child’s mid-20s.
Some brain changes happen before puberty, and some continue long after. Brain change depends more on age and experience, not on when puberty starts. So even if your child started puberty early, this doesn’t necessarily mean that brain changes started early too.
Adolescence is a time of significant growth and development inside the teenage brain.
The main change is that unused connections in the thinking and processing part of your child’s brain (called the grey matter) are ‘pruned’ away. At the same time, other connections are strengthened. This is the brain’s way of becoming more efficient, based on the ‘use it or lose it’ principle.
This pruning process begins in the back of the brain. The front part of the brain, the prefrontal cortex, is remodelled last. The prefrontal cortex is the decision-making part of the brain, responsible for your child’s ability to plan actions, solve problems and control impulses. Changes in this part continue into early adulthood.
Because the prefrontal cortex is still developing, teenagers might rely on a part of the brain called the amygdala to make decisions and solve problems more than adults do. The amygdala is associated with emotions, impulses, aggression and instinctive behaviour.
The combination of your child’s unique brain and environment influences the way your child acts, thinks and feels. For example, your child’s preferred activities and skills might become ‘hard-wired’ in the brain. How teenagers spend their time is crucial to brain development. So it’s worth thinking about the range of activities and experiences your child is into – music, sports, study, languages, video games. How are these shaping the sort of brain your child takes into adulthood?
You are an important part of your child’s environment. Your relationship with your child – as well as how you guide and influence him – will be important in helping your child to build a healthy brain.
You can do this by:
Encouraging positive behaviour
While your child’s brain is developing, your child might:
Here are some tips for encouraging desirable behaviour and strengthening positive brain connections:
Promoting thinking skills
Brain growth and development during these years mean that your child will start to:
You can support the development of your child’s thinking with the following strategies:
Getting lots of sleep
During the teenage years, your child’s sleep patterns will change. This is because the brain produces melatonin at a different time of the day. This makes your child feel tired and ready for bed later in the evening. It can keep your child awake into the night and make it difficult to get up the next morning.
Sleep is essential to healthy brain development. Try the following tips:
The teenage brain is built to seek out new experiences, risks and sensations – it’s all part of refining those brain connections.
But the self-monitoring, problem-solving and decision-making part of the brain – the prefrontal cortex – develops last. This means that teenagers don’t always have a lot of self-control or good judgment, and are more prone to risk-taking behaviour. Hormones are also thought to contribute to impulsive and risky behaviour in teens.
With so many changes happening to your child’s brain, it’s especially important that your child is protected and nurtured.
The incidence of poor mental health increases during the teenage years. It’s thought this could be related to the fact that the developing brain is more vulnerable to stress factors than the adult brain. For teenagers, stresses can include drugs, alcohol and high-risk behaviour.
But don’t wrap your child in cotton wool! Too much parental attention might alienate your child.
Staying connected and involved in your child’s life can help you to learn more about how your child is coping with stress. It can also help you keep an open relationship with your child and ensure that your child sees you as someone to talk to – even about embarrassing or uncomfortable topics.
Every child experiences changes at a different rate. If you’re concerned about your child’s rate of development or you have concerns about your child’s changing body, thinking skills or behaviours, you could start by talking to a school counsellor or your GP. If you’re really worried, you could look for a counsellor or psychologist. You don’t need a referral, but might prefer to have your GP recommend someone.
Centre for Adolescent Health, The Royal Children’s Hospital, Melbourne.
Australian Broadcasting Corporation. Catalyst: Teen Brain (28 July 2005). Retrieved March 4, 2010, from http://www.abc.net.au/catalyst/stories/s1424747.htm#
Australian Government, Department of Health and Ageing. (2006) Teenagers and alcohol: a guide for parents. Retrieved March 4, 2010, from
http://www.alcohol.gov.au/internet/alcohol/publishing.nsf/content/4576756CA5268C8ECA25719400181178/$File/brochure-teen-alcohol.pdf
Barnes G. M. et al (2000). The effects of parenting on the development of adolescent alcohol misuse: A six-wave latent growth model. Journal of Marriage and the Family, 62, 175-186.
Bessant, J. (2008). Hard wired for risk: neurological science, ‘the adolescent brain’ and developmental theory. Journal of Youth Studies, 11, 3, 347-360.
Bruck, Dorothy (2006) Teenage sleep: Understanding and helping the sleep of 12-20 year olds. Wellness Promotion Unit, Victoria University, Melbourne. E-book. Retrieved April 28 2010 from http://eprints.vu.edu.au/467/
Casey, B. J., Jones, R. M. & Hare, T.A. (2008). The adolescent brain. Annals of the New York Academy of Sciences, 1124, 111-126.
Dahl, R. E. (2004). Adolescent brain development: a period of vulnerabilities and opportunities. Annals of the New York Academy of Sciences, 1021, 1-22.
Galvan, A. et al. (2007). Risk-taking and the adolescent brain: who is at risk? Developmental Science, 10, 2, F8-F14.
Giedd, J. N. (2009). Editorial: Linking adolescent sleep, brain maturation, and behaviour. Journal of Adolescent Health, 45, 319-320.
Patton, G. C. & Viner, R. (2007). Pubertal transitions in health. The Lancet, March, 369 (9567), 1130-9.
PBS: Inside the Teenage Brain. Interview with Dr Jay Giedd. Retrieved March 5, 2010, from
http://www.pbs.org/wgbh/pages/frontline/shows/teenbrain/interviews/giedd.html
Ponton, L. 10 Tips for Parents of Risk-taking Teenagers. Retrieved March 16, 2010, from http://psychcentral.com/lib/2006/10-tips-for-parents-of-risk-taking-teenagers/
Powell, E. (2004). Studying Functional Differences in the Adolescent Brain May Provide Evidence that the Nervous System is Responsible for Behavior. Retrieved March 29, 2010, from http://serendip.brynmawr.edu/bb/neuro/neuro04/web1/epowell.html
Powell, K. (2006). How does the teenage brain work? Nature, 442, 24, 865-867.
Wallis, C. (26 Sept 2008). What makes teens tick. Time. Retrieved March 5, 2010, from http://www.time.com/time/magazine/article/0,9171,994126,00.html