The most important thing for you as a parent of a teenager to understand is that your teenager’s brain is undergoing enormous change. This change isn’t your teenager being difficult, rebellious and rude for no reason – it’s a stage of development called adolescence where a child transitions towards a young adult stage of life. This is both a physical transition, in terms of being sexually mature, and a psychological transition in terms of seeking some independence from the family setting and looking outwards to peer groups.
During this period of brain development, the hormone-fuelled limbic system temporarily takes charge.
The way traditional ‘teenage’ rebellious and risk-taking behaviour occurs is due to a mismatch of development between two specific regions of the teenage brain – namely, the pre-frontal cortex, which “controls” the thinking part of our brains, and the limbic system, which is associated with emotions and gut reactions.
Simply put, the hormone-driven limbic system in teenagers starts developing massively at the onset of puberty – around 10-12 years old. This means emotional, risk-taking, and rebellious behaviour comes to the fore. On the other hand, the pre-frontal cortex, which in adults serves as a “control centre” for being emotional or overly-risk-taking behaviour – isn’t well developed until much later.
Scientists now understand that the pre-frontal cortex continues to develop well into a person’s 20s. This means there is a fundamental mismatch in development – with the emotional limbic system “over-riding” the more “adult” or controlled prefrontal cortex for a period of up to around 10 years.
So your teenage daughter coming home with dyed hair and a piercing, or your teenage son arguing with you over “nothing” and seemingly hating you – isn’t necessarily a sign of something wrong in their development or your family relationships – but rather something a “normal” developmental phase which needs to be understood to be dealt with productively.
Such awareness of these teenage norms can help you as a parent to distinguish “normal” adolescent rebellion and impulsivity with more worrying behaviour. Understanding teenagers’ behaviour in this way might help communities and society at large to reduce the rates of teen addiction, sexually transmitted diseases, depression, self-harm and suicide.
Brain imaging studies of teenager’s brains performing a range of tasks have helped psychologists and neurologists to understand how brain architecture and connectivity changes during puberty and how it affects teenagers’ behaviour and thinking capacities.
Professor Yurgelun-Todd and her colleague Marisa Silveri have reported that poor judgment and risky behaviour in teenagers might be due to healthy and normal changes in the white matter microstructure in the brain’s prefrontal cortex. The brain’s frontal cortex is associated with executive functions like:
During puberty lots of unneeded gray matter, in the frontal cortex, is pruned away while white matter (fast myelin-covered neurons), increases. This myelination is like insulation of electrical wires and speeds up and improves connectivity. Yurgelun-Todd and Silveri found the more connected the prefrontal white matter, the stronger the self-reported impulse control in boys and the actual impulse control in teenage girls. This helps us to understand how the development of the frontal and prefrontal cortex may lead to improved impulse control.
In an earlier study, Yurgelun-Todd reported that three-quarters of teenagers did not recognise fearful faces and were significantly less able than adults to read emotions in faces. Also, the frontal cortex showed low neural activity when shown angry and fearful faces. Reading fear in the faces of other people is a vital way by which we judge how safe a situation is. If teenagers are unable to see fear in their peers they are perhaps more likely to underestimate the danger of a particular act e.g., drink driving or driving too fast.
In many ways, the teen years are the healthiest strongest years of a human’s life – the immune system, physical strength – many physical traits are at their greatest.
Risk taking behaviour mightn’t have been so risky in our cave-dwelling days – but when coupled with access to motor-cars, alcohol, drugs and firearms (in some societies), it becomes very risky indeed. Motor accidents are sadly the number one cause of teen deaths – the cause of around half of them. Homicide and suicide rank second and third. Unwanted pregnancies are also high at this age, with potential tough consequences.
The teenage years are the peak time for the emergence of many types of mental illness including substance abuse, depression, bipolar disorder, anxiety and eating disorders. Interestingly, many of the abnormal brain findings in adult schizophrenia resemble a teenage brain “gone too far.”
The most important thing you can do is to be aware of what is going on in your teenager’s brain. Your teenager is not necessarily trying to be difficult. His brain development is driving him to distance himself, a bit, from you. However, in this new independent state he will struggle to assess risks and read emotions in people’s faces.
This is temporary and your teenager is not a “lost cause.” All being normal, his “thinking” brain will continue to develop into his early 20s. It must also be said that not all teenagers are markedly rebellious or risk taking and this is down to a range of factors including:
You can encourage the move away from the family so it’s more thought-through and positive.
Many ancient cultures had rites of passage performed on girls and boys at the time of the onset of puberty. Boys were often taken from their mothers and fathers and taken out for an initiation ceremony with the men of the tribe – perhaps being made to do something brave like fight a wild animal, or being left on their own for some time.
These days this sort of rite of passage isn’t perhaps appropriate – but this ancient rite can be considered in more modern ways. A “mentor” for your teenager is an extremely important person. Somebody chosen by him, and/or you. Perhaps someone who can take him away from the family unit for periods of time and mentor them in something he excels at or enjoys. Art, sport, trekking, computers – whatever it may be. The more you can encourage this as a parent – the less desperate your teenager will be to create distance from you and the family unit.
Xu, Murphy, Kochanek, Brigham & Bastian (2016) Deaths: Final Data for 2013. National Vital Statistics Reports Volume 64, Number 2 February 16, 2016
Arialdi & Miniño (2010) Mortality Among Teenagers Aged 12-19 Years: The United States, 1999-2006 NCHS Data Brief No. 37, May 2010
Rosso, I.M., Young, A.D., Femia, L.A. & Yurgelun-Todd, D.A. (2004). Cognitive and emotional components of frontal lobe functioning in childhood and adolescence. Annals of the New York Academy of Sciences, 1021, 355-362.
Yurgelun-Todd, D.A. & Killgore, W.D.S. (2006) Fear-related activity in the prefrontal cortex increases with age during adolescence: A preliminary fMRI study. Neuroscience Letters, 406, 194-199.
Yurgelun-Todd, D. (2007) Emotional and cognitive changes during adolescence. Curr Opin Neurobiol, Apr;17(2):251-257.