1. Understanding
Teen Behaviour

3. Adolescence is also a time
when many new behaviours
begin to emerge, most of which
irritate and frustrate parents!

4. Typical teenage behavioural
changes include:
Changes in ATTENTION
Changes in MOTIVATION
Changes in RISK-TAKING behaviour
You might be surprised to learn that many
adolescent behaviours are a direct result of brain
changes, and are completely normal!

5. ATTENTION: Are you listening?
Many cognitive abilities
(including the control of
attention) rely on the proper
functioning of a part of the brain
called the prefrontal cortex.
BUT… the prefrontal cortex
undergoes massive structural
changes during adolescence,
and it is one of the last brain
areas to mature completely!

6. ATTENTION: Improves with age
In one study, researchers used two tasks to measure attention in
adolescents, and performance increased with age.
boys
girls
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)

7. MOTIVATION: “I don’t care…”
“She won’t make her bed! She lives
like a pig! I don’t know what to do!”
“Leave me alone…”
“Why won’t she just do
what I ask her to do?”
“I don’t want to…”
“He won’t study! Doesn’t he realize that
he won’t pass if he doesn’t study?”
“I don’t care…”

8. MOTIVATION: Adults vs. Teens
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)

9. MOTIVATION: “Get Movin’ Kid!”
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.

10. What does this mean for
me??
Most teenagers are more likely to do their
homework for a PhP5 reward TONIGHT than
for a PhP50 reward next week!

11. 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)

12. 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)

13. RISK-TAKING
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)!
(Spear, 2000)

14. RISK-TAKING
Risk-taking might allow teens to:
• Explore adult behaviour and
privileges
• Accomplish normal
developmental tasks
• Learn from their mistakes
BUT, risk-taking
carries potential for
negative outcome!!
(Spear, 2000)

15. RISK-TAKING: What are the stats?
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)
The pregnancy rate in girls 15-19 years old is 4/100
(The Walrus, Nov 2006)
3 million adolescents contract sexually transmitted
infections every year
(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)

16. RISK-TAKING: Impulsivity
 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.
 Luckily, as the brain matures, adolescents
are more able to control their behaviour
and are more able to voluntarily suppress
impulsive behaviours.
 This is because as the brain matures,
more brain circuits are recruited to help
suppress impulsivity!
 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!

17. RISK-TAKING: The neural basis for
“What the heck were you thinking?!”
 When teenagers and adults are faced with
potential rewards, their brains respond
VERY differently.
 In teenagers, the maturing “reward”
systems (photo A) are disproportionately
active relative to later maturing “control”
systems (photo C).
 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!
Galvan et al. (2006)

18. RISK-TAKING: What do we do?
Adolescence is generally a period
of increased impulsivity and risk-
taking behaviour, but some teens
might be especially prone to
engage in such behaviours.
So what do teens
NEED?
Galvan et al. (2007)

19. Teenagers need the influence,
patience, understanding and

20. They need reminders of potential
consequences and direction
toward lesser risks…

21. And they need appropriate
amounts of independence,
freedom and responsibility.

22. 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.

23. Sun Life Financial Chair
In Adolescent Mental Health
For more information visit
WWW.TEENMENTALHEALTH.ORG