Adolescence is a time of growth and maturation in the brain, and it is also a time when many new behaviours begin to emerge (most of which irritate and frustrate parents!). These changes include changes in attention, in motivation and in risk-taking behaviour. Surprisingly, many of these behaviours are a direct result of brain changes, and are completely NORMAL!
Adolescence is a time of growth and maturation in the brain.
Adolescence is also a time when many new behaviours begin to emerge, most of which irritate and frustrate parents!
Changes in RISK-TAKING behaviour Changes in ATTENTION Changes in MOTIVATION You might be surprised to learn that many adolescent behaviours are a direct result of brain changes, and are completely normal ! Typical teenage behavioural changes include:
BUT… the prefrontal cortex undergoes massive structural changes during adolescence, and it is one of the last brain areas to mature completely! Many cognitive abilities (including the control of attention) rely on the proper functioning of a part of the brain called the prefrontal cortex . ATTENTION: Are you listening?
In one study, researchers used two tasks to measure attention in adolescents, and performance increased with age. girls boys This might mean that older adolescents have a better attentional capacity than younger adolescents, and that attentional capacity improves as the brain matures. Thank goodness! Anderson et al. (2001) ATTENTION: Improves with age
“ She won’t make her bed! She lives like a pig! I don’t know what to do!” “ I don’t care…” “ I don’t want to…” “ Why won’t she just do what I ask her to do?” “ Leave me alone…” “ He won’t study! Doesn’t he realize that he won’t pass if he doesn’t study?” MOTIVATION: “I don’t care…”
One study looked at the differences in motivation between adults and teenagers. The researchers compared the brain activation of adults and teenagers while they were performing the same task for a reward. Compared to adults , teenagers under-use the brain circuits that are involved in motivation! Bjork et al. (2004) MOTIVATION: Adults vs. Teens
This under-use of the motivational system might be the reason why teenagers need extreme rewards to achieve the same level of brain activity as adults. AND… the difference in brain activity between teenagers and adults can be even LARGER when the reward is not instant. MOTIVATION: “Get Movin’ Kid!”
Most teenagers are more likely to do their homework for a $5 reward TONIGHT than for a $50 reward next week! What does this mean for me??
MOTIVATION: It takes time The primary motivation circuit helps promote decision making and helps in the selection of motivational drives for behaviour. The motivational drives that are represented in the primary motivation circuit change during puberty (for example, surges in sex hormones tend to increase sexual motivation). Chambers et al. (2003)
MOTIVATION: It takes time During these developmental changes in motivation circuitry, novelty-seeking and risk-taking behaviours might be promoted. However, as adolescence progresses, teens become increasingly motivated by the things that motivate adults (boring, responsible things like long-term rewards!) Chambers et al. (2003)
Teenagers are known for risk-taking, novelty seeking, reckless behaviour and impulsivity. Believe it or not, some degree of risk-taking in adolescence is normative (and adaptive)! <ul><ul><ul><li>(Spear, 2000) </li></ul></ul></ul>RISK-TAKING
<ul><ul><ul><li>(Spear, 2000) </li></ul></ul></ul><ul><li>Risk-taking might allow teens to: </li></ul><ul><li>Explore adult behaviour and privileges </li></ul><ul><li>Accomplish normal developmental tasks </li></ul><ul><li>Learn from their mistakes </li></ul>BUT, risk-taking carries potential for negative outcome!! RISK-TAKING
16-20 year olds (males AND females) are twice as likely to be in car accidents than 20-50 year olds (Sci. Am. Mind, Jan 2007) 10-14% of adolescents are problem gamblers , and most of these teens started gambling by the age of 12 (Sci. Am. Mind, Jan 2007) 14-19 year olds are more likely to commit property crimes or violent offences than any other age group (The Walrus, Nov 2006) 3 million adolescents contract sexually transmitted infections every year (Sci. Am. Mind, Jan 2007) The pregnancy rate in girls 15-19 years old is 4/100 (The Walrus, Nov 2006) RISK-TAKING: What are the stats?
<ul><li>The adult-like ability to inhibit behaviours matures gradually during childhood and adolescence, and efficient control of impulsive acts is not fully developed until adulthood! </li></ul><ul><li>The teenage brain is less able to inhibit impulsive behaviours than the adult brain is. This means that in situations where an adult might stop themselves from acting out impulsively, a teenager might not. </li></ul><ul><li>Luckily, as the brain matures, adolescents are more able to control their behaviour and are more able to voluntarily suppress impulsive behaviours. </li></ul><ul><li>This is because as the brain matures, more brain circuits are recruited to help suppress impulsivity! </li></ul>RISK-TAKING: Impulsivity
Galvan et al. (2006) <ul><li>In teenagers, the maturing “reward” systems (photo A) are disproportionately active relative to later maturing “control” systems (photo C). </li></ul><ul><li>This biases their actions toward immediate gain rather than long-term gain. This just might underlie some of the risk-taking behaviours that occur during adolescence! </li></ul><ul><li>When teenagers and adults are faced with potential rewards, their brains respond VERY differently. </li></ul>RISK-TAKING: The neural basis for “What the heck were you thinking?!”
Adolescence is generally a period of increased impulsivity and risk-taking behaviour, but some teens might be especially prone to engage in such behaviours. RISK-TAKING: What do we do? Galvan et al. (2007) So what do teens NEED?
Teenagers need the influence, patience, understanding and guidance of parents…
They need reminders of potential consequences and direction toward lesser risks…
And they need appropriate amounts of independence, freedom and responsibility.
References Anderson, V.A., Anderson, P., Northam, E., Jacobs, R., Catroppa, C. 2001. Development of executive functions through late childhood and adolescence in an Australian sample. Developmental Neuropsychology. 20: 385-406. Bjork, J.M., Knutson, B., Fong, G.W., Caggiano, D.M., Bennett, S.M., Hommer, D.W. 2004. Incentive-elicited brain activation in adolescents: similarities and differences from young adults. The Journal of Neuroscience. 24: 1793-1802. Chambers, R.A., Taylor, J.R., Potenza, M.N. 2003. Developmental neurocircuitry of motivation in adolescence: A critical period of addiction vulnerability. American Journal of Psychiatry. 160: 1041-1052. Galvan, A., Hare, T.A., Parra, C.E., Penn, J., Voss, H., Glover, G., Casey, B.J. 2006. Earlier development of the accumbens relative to orbitofrontal cortex might underlie risk-taking behavior in adolescents. The Journal of Neuroscience. 26: 6885-6892. Galvan, A., Hare, T.A., Voss, H., Glover, G., Casey, B.J. 2007. Ris-taking and the adolescent brain: Who is at risk? Developmental Science. 10: F8-F14. Luna, B., Thulborn, K.R., Munoz, D.P., Merriam, E.P., Garver, K.E., Minshew, N.J., Keshavan, M.S., Genovese, C.R., Eddy, W.F., Sweeney, J.A. 2001. Maturation of widely distributed brain function subserves cognitive development. NeuroImage. 13: 786-793. Spear, L.P. 2000. The adolescent brain and age-related behavioral manifestations. Neuroscience and Biobehavioral Reviews. 24: 417-463. “ Is the teen brain too rational?”. In: Scientific American Mind, January 2007. “ The teenage brain”. In: The Walrus, November 2006.
Sun Life Financial Chair In Adolescent Mental Health For more information visit WWW.TEENMENTALHEALTH.ORG