Adolescent Growth and Development Angela Huebner, Ph.D. Associate Professor Department of Human Development Virginia Tech ahuebner@vt.edu 703.538-8491 February 7, 2008

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

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

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

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

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

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

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

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

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)

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)

Bottom Line?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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