1. Adolescent Growth and Development
Angela Huebner, Ph.D.
Associate Professor
Department of Human Development
Virginia Tech
February 7, 2008

2. Period of Adolescence Rapid growth
Interaction of physical, psychological, and environmental factors
Off timing of systems (Dahl, 2004)
Puberty
Physical growth
Emotion and behavior regulation
Importance of understanding interaction of all the systems;
Transitions all occur sequentially but not necessarily at the same time
2 developmental processes
Puberty and cognitive development; progress at different rates
“starting the engine with an unskilled driver”
“igniting passions”
Have ‘turbo charged feelings” with learners permit driving skills

3. Source: Cooperative Extension System
Extension "CARES" for America's Children and Youth Initiative
March, 2001

4. What’s the Big Deal? Adolescent morbidity Health Paradox (Dahl, 2004):
Developmental period of strength and resilience both physically and cognitively
Yet, morbidity & mortality rates increase 200%
DIFFICULTIES IN CONTROLLING BEHAVIOR AND EMOTION
Compared to young children, adolescents are stronger, bigger, and faster and are achieving maturational improvements in reaction time, reasoning skills, immune function and the capacity to withstand cold, heat, injury, and physical stress
Also illustrate better reasoning and decision making skills than young children
**What accounts for morbidity? Major sources are related to difficulties in the control of behavior and emotion
It’s high rates of accidents, suicide, homicide, depression, ATOD, violence, reckless behavior, risky sex…
DIFFICULTIES IN CONTROLLING BEHAVIOR AND EMOTION—MOST RECKLESS DECISIONS ARE EMOTIONALLY BASED

5. Overview I. Physical Development II. Cognitive Development
III. Psycho-Social Development

6. I. Physical Development
Height & Weight Changes
Secondary Sex Characteristics
Continued Brain Development

7. Rapid Gains in Height & Weight
4.1 to 3.5 inches per year
Girls mature about 2 years earlier than boys
Weight gain = muscles for boys; fat for girls

8. Secondary Sex Characteristics:
Pubic hair
Menarche or penis growth
Voice changes for boys
Underarm hair
Facial hair growth for boys
Increased production of oil, sweat glands, acne

9. Continued Brain Development
Not completely developed until late adolescence
Emotional, physical and mental abilities incomplete
May explain why some seem inconsistent in controlling emotions, impulses, and judgements

10. Understanding the Adolescent Brain
Advances in brain imaging allow for better understanding of what occurs
Evidence for frontal lobe delays Inability to delay gratification; impulse control
Suggestion that puberty represents a period of synaptic reorganization and as a consequence the brain might be more sensitive to experiential input at this period of time in the realm of executive function and social cognition
Prefrontal cortex of interest
Executive function=capacity that allows coordination of thoughts and behaviors—selective attention, decision making, voluntary response inhibition and working memory
e.g. allows you to filter out unimportant information, holding in mind a plan to carry out in the future and inhibiting impulses
PREFRONTAL CORTEX
Involved in multiple aspects of cognitive processing
It’s a proposed mediator of behavioral planning and reasoning, attentional processes, impulsivity and response inhibition
Given this the contention is that some adol who experiment with ATOD may not be able to moderate their impulsivity—and consider alternative behavioral choices and consequences—or to inhibit a response
(Blakemore & Choudhury, 2006)

11. Brain: Developmental Changes
Synaptogenesis: proliferation of synapses
Myelinazation: insulation around synapses
Synaptic pruning: frequently used connections are strengthened, infrequently used connections are eliminated
Normative synaptogensis and pruning—0-3 literature—sensitive periods—e.g. language development—unused areas are eliminated
Most of this is linear with the exception of the prefrontal cortex
Suggested that prefrontal cortex pruning is ignited during puberty but continues up until age 30!
(Blakemore & Choudhury, 2006)

12. Bottom Line?

13. How do these change affect teens?
Usually studied as decision making (Steinberg, 2004)
In lab: similarities in adolescent & adult decision making processes
Adolescents are uniquely vulnerable to risk taking
Novelty & sensation seeking increase dramatically at puberty
Development of self-regulation lags behind
Risk taking as group behavior (Steinberg, 2004)
We have historically tried to understand adol risk taking by focusing on their decision making process
Results show that risk perception and appraisal change very little between adolescence and adulthood
In laboratory settings, adolescents appear quite similar to adults in their decision making process
Flaws in methods-
Give hypothetical scenarios which negates emotional element
Study adol individually, but risk behavior tends to occur in groups
Steinberg (2004) suggests that “the greater propensity for adolescents to take risks is not due to age differences in risk perception or appraisal, but to age differences in psychosocial factors that influence self-regulation”
Adolescents is a heightened vulnerability to risk taking because of a disjunction between novelty and sensation seeking (both of which increase dramatically at puberty) and the development of self-regulatory competence (which does not fully mature until early adulthood) which is biologically driven and normative.
Interventions should aim to reduce the harm associated with risk taking

14. How Do These Changes Affect Teens?
Frequently sleep longer - 9 1/2 hours
May be more clumsy because of growth spurts-body parts grow at different rates
Girls may become sensitive about weight - 60% trying to lose weight
1-3% have eating disorder

15. How Do These Changes Affect Teens?
Concern if not physically developing at same rate as peers - need to “fit” in (early vs. late maturation)
Feel awkward about showing affection to opposite sex parent
Ask more direct questions about sex - trying to figure out values around sex

16. What Can Adults Do?
Expect inconsistency in responsibility taking and in decision making
Provide opportunities for “safe” risk taking
Avoid criticizing/comparing to others
Encourage enough sleep
Encourage/model healthy eating
Encourage/model activity
Provide honest answers about sex

17. II. Cognitive Development
Advanced Reasoning Skills
Abstract Thinking Skills
Meta-Cognition

18. Beginning to Gain Advanced Reasoning Skills
Options
Possibilities
Logical
Hypothetically
What if?

19. Think Abstractly Can take others’ perspective
Can think about non-concrete things like faith, trust, beliefs, and spirituality

20. Ability to Think About Thinking
Meta-cognition
Think about how they feel and what they are thinking
Think about how they think they are perceived by others
Can develop strategies for improving their learning

21. How Do These Changes Affect Teens?
Heightened self-consciousness
Believes no one else has experienced feelings/emotions
Tend to become cause-oriented
Tend to exhibit a “justice orientation”
“It can’t happen to me” syndrome

22. What Can Adults Do?
Don’t take it personally when teens discount experience
Discuss their behavior rules/consequences
Provide opportunities for community service
Ask teens their view and share own

23. III. Psycho-Social Development
Establishing identity
Establishing autonomy
Establishing intimacy
Become comfortable with one’s sexuality
Achievement

24. Establishing Identity
Erikson (1959): identity vs. identity diffusion
Integrates opinions of other into own likes/dislikes—needs interactions with diverse others for this to occur
Outcome is clear sense of values, beliefs, occupational goals, and relationship expectations
Secure identities-knows where they fit

25. Identity Exploration Process:
Commitment
present
absent
Identity
Achievement
Foreclosure
Moratorium
Diffusion
present
Exploration
absent
Marcia (1966)

26. Establishing Autonomy
Becoming independent and self-governing within relationships
Make and follow through with decisions
Live with own set of principles of right/wrong
Less emotionally dependent on parents

27. Establishing Intimacy
Learns intimacy and sex not same thing
Learned within context of same-sex friendships; then in romantic relationships
Develops close, open, honest, caring, and trusting relationships
Learn to begin, maintain, and terminate relationships; practice social skills, and become intimate from friends

28. Becoming Comfortable with One’s Sexuality
How educated/exposed to sexuality largely determines if healthy sexual identity develops
More than half high school students are sexually active
Mixed messages contribute to teen pregnancy and sexually transmitted diseases

29. Predictors of Sexual Activity
Having a steady boy/girlfriend
Using alcohol regularly
Having parents with permissive values about sex
Being worried about one’s future occupational success
Implication: focus on more than one risk factor

30. Achievement
Society fosters and values attitudes of competition and success
Can see relationship between abilities, plans, aspirations
Need to determine achievement preferences, what good at, and areas willing to strive for success

31. How Do These Changes Affect Teens?
More time with friends
May keep a journal
More questions about sexuality
Begin to lock bedroom door
Involved in multiple hobbies/clubs
More argumentative
Interact with parents as people

32. What Can Adults Do? Encourage involvement in groups
Praise for efforts and abilities
Help explore career goals and options
Help set guidelines/consequences
Establish rituals for significant passages
Know friends and what they are doing
Provide structured environment/clear expectations