Transcript Chapter 11-12 Adolescence

Adolescence
Psyc311 Developmental
Dr. Wright
definition of puberty
• Pubertas – Latin word for “adult”
• Narrow definition: The process by
which an individual becomes
capable of reproduction.
– The activation of the HPG/HPA axis
• Broad definition: The physical,
psychological, and cultural changes
that occur as the growing child
transitions into adulthood.
time periods of adolescent
• Adolescence is a unique developmental period
– it keeps changing!
• Early adolescence – 11 to 13 years old
– Continues to be pushed earlier (9-10…)
• Middle adolescence – 14 to 17 years old
• Late adolescence (early adulthood) – 18 to 20
years old
– Continues to be pushed later (21-24…)
physical changes…
 Primary sex characteristics
• The body organs and reproductive structures and
functions that differ between women and men.
• Gonads (testes and ovaries)
 Secondary sex characteristics
• Characteristics of the body that are caused by hormones,
develop during puberty, and last through adult life.
• Changes in genitals/breasts/voice
• Pubic/body/facial hair
Tanner Stages
Tanner Stages
changes…
 Rapid acceleration of physical growth
• Adolescent growth spurt
• 3.5 (girls) to 4.0 (boys) inches/year
• ½ adult weight gained during adolescence
 Changes in body composition
• 3:1 muscle to body fat ratio for boys
• 5:4 for girls
• Emergence of sex differences in physical
performance
 Changes in circulatory and respiratory systems
• Increase in size/capacity of heart and lungs
two roles of hormones
 Organizational role (life-long):
– Modification of the organism early in life
• primarily influencing its anatomy
– Organization/structure of CNS
• “Feminine” vs. “masculan-ized” brain and body
 Activational role (specific to puberty):
– Structural “remodeling” of brain
– Increase in salience of sexual stimuli, sexual motivation
– Development of secondary sex characteristics
hormone regulatory systems
• Endocrine system
• HPA axis
– Hypothalamus  Pituitary gland  Adrenals
– Corticosteroids
– Regulates body’s response to stress
• HPG axis
– Hypothalamus  Pituitary gland  Gonads
(Testes/Ovaries)
– Sex Hormones (Androgens/Estrogens)
– Regulates sexual maturation
The hormonal changes brought on by puberty
can affect the adolescent’s behavior in at least
three ways.
impacts of puberty
• Sleep patterns
– Delayed phase preference
– 9 hours: 1 am to 10 am
• Family relations
– Transformation of parent-child bond
• Peer relations
– Transformation of friendships, romantic
relationships
impacts of puberty
• Self-esteem
– Changing body image
– Changing sense of self
• Moods
– Increased stress + Increased sensitivity
• Fluctuation of moods
– Due to hormones or environment?
– “Storm and stress”: myth or fact?
moods
timing - individual factors
• Genetic factors
– Timing and tempo
• Environmental factors
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Nutrition
Body weight
Exposure to hormones/chemicals
Family conflict
Stepfathers
timing - group factors
• Comparisons
• Across socioeconomic groups
– Impact of poverty
– Dietary intake, health care, exposure to disease
• Across countries
– Impact of industrialization
• Across time periods
– Secular trend
early maturation
• Boys
– Early maturation positives
• Popularity, higher self-esteem
– Early maturation negatives
• Deviant, risk behaviors; more rigidity later
• Girls
– Early maturation positives
• Popularity (cultural dependence)
– Early maturation negatives
• Lower self-esteem, eating disorders, emotions, deviant behaviors
late maturation
• Boys
– Late maturation positives
• Higher levels of creativity, inventiveness
– Late maturation negatives
• Low self-esteem, low social competence
• Girls
– Late maturation positives
• Thinner build
– Late maturation negatives
• Social withdrawal
the second wave….
Longitudinal fMRI studies reveal:
• Period of rapid synaptogenesis and pruning
• Increased myelination (back to front)
• Opportunity for massive cognitive growth and
learning
– Shift into Piaget’s formal operations
Among the most
important
changes to take
place in the
adolescence
brain are those
in the prefrontal
cortex and limbic
system.
(pre) frontal development
• Final development of executive function
– Planning/problem-solving
– Impulse control
– Seat of “sober 2nd thought”
• Full maturation – sometime between
adolescence and early adulthood
• Coincides with child-onset schizophrenia
– Failure in executive functioning
heightened arousal
• Increased hormone activity
– estrogen & testosterone
• Sexual stimulation
• Social status conflict
• Increased neurotransmitter activity
– heightened emotional sensitivity/reactivity
• Limbic system (norepinephrine)
– increased risk, stimulation-seeking behaviors
• Punishment/reward system (dopamine)
– increased fluctuations in mood
• Serotonin
timing of brain maturation
• Limbic system matures early in puberty
• Prefrontal cortex matures several years later
• Heightened need for reward/stimulation
– leads to increased risk-taking, stimulation-seeking
behaviors
• Higher level of emotional volatility
• Underdeveloped “sober” assessment of risks
• Increased cognitive/social demands
– Creates cognitive overload
– Difficulty with impulse control
timing of brain maturation
• Time gap may explain why adolescence is a
period of heightened experimentation with
risky behaviors.
• Increased risk of
– violence/criminal activity
• kids under 18 account for 25 of violent crime in US
– drug & alcohol experimentation
– unsafe sexual activities
conduct problems
Adolescents whose
prefrontal cortical
development is less mature
than normal are even more
likely to have conduct
problems.
Populations most at risk?
teen pregnancy
teen pregnancy in US
• 750-850,000 teens between 15-19 years old become
pregnant every year.
– 2/3rds between 18-19 years old.
– 25,000 under 15 years old.
• African American teens have highest rate
– 134/1,000 vs. 48/1,1000 Caucasian teenagers
• 57% end in birth (11% of all births in US)
– 14% end in miscarriage
– 29% end in abortion
• 82% of those pregnancies were unintended
• 86% of teen mothers remain unmarried
• 35% have a 2nd child within two years
risk factors
 Physical
• Sexual maturation
– 4-5 years before psychological/emotional maturation
– Becoming longer as puberty starts earlier
• Brain development
– Heightened activation of limbic system
– Increased attraction to risky behaviors
– Pre-frontal development incomplete
Why is teenage pregnancy higher in the US?
consequences
• SES factors
– 50% of pregnancies occur in most impoverished
populations
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Less opportunity for education
Less access to birth control
Reduced internal locus of control
Exposure to other risk factors
– drugs, alcohol, abuse, lack of parental monitoring
• Desire for family/stability
consequences
• Should we be concerned about this?
• For teenage parents
– mother in particular
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For baby
For families
For community
Methods of prevention?
adolescent substance use
• Have tried, by grade 10:
– cigarettes – 40%
– alcohol – 63%
– illegal drugs – 38%
• By end of high school:
– 17% smoke regularly
– 28% recent heavy drinking
– 40%+ tried illegal drugs
Figure 11.7
impact of substance abuse
• Alcohol/drug abuse
– Greater potential impairment in learning
– More widespread brain damage
– Repeated exposure may effect path and quality of
development
– Due to reduction in plasticity, this damage cannot
be corrected later!
• So, does this mean all experimentation with
drugs/alcohol bad?
adolescent substance abusers
• Compared to experimenters:
– more antisocial, impulsive acts
– start earlier
– more likely to be affected by
genetic and environmental factors
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low SES
family drug use
family difficulties
physical, sexual abuse
poor school performance
• Should we be worried about exposure to
graphic violence through media?
– Why or why not?
• What reasons might we have for thinking
adolescents are particularly vulnerable to
aggression/violence?
social implications
• What should the social attitudes be about
adolescent exposure to and involvement in
high-stimulation/high-risk activities?
• Sexual Activity
• Drugs & Alcohol
• Violence
identity development
• Adolescence  Erickson stage of identity crisis
• Identity
– Sense of individual self
– Selection of commitments, beliefs, values
• Interpersonal process
– Taking their place in the adult community
cognitive changes
• Importance of conceptual structure of thinking
 Propositional logic: thinking constrained by logical relations
– Emphasis on rationality and scientific methodology
• Importance of conceptual resources employed
in thinking
 Five process: Attention, working memory, processing speed,
organization, meta-cognition
cognitive changes
• Piaget’s – Formal Operational Thought
– Logical, abstract thinking
• Thinking about possibilities
– “If-then” thinking
– Connection between how things are and how they
might have been or could be.
• Thinking about thinking
– Understanding knowledge (how/when gained)
– Monitoring one’s own mental states
relativism
• Not everything is “black and white”
– Recognition of importance of perspective
– Death of childish “realism/absolutism”
 Can result in extreme skepticism
• Rejection of authority
• Rejection of cultural/social norms
• Everything is “ok” – no right/wrong
 Tolerance for different beliefs
• Though less tolerance for actual interaction/helping
adolescent egocentrism
• Increased introspection, self-consciousness,
rationalization
• Responsible for adolescent version of
egocentrism.
– Imaginary audience
– Personal fable
– Importance of personal individuality
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Crisis never begins: diffusion
Crisis begins –> ends with foreclosure
Crisis begins –> ends with achievement
Psychosocial moratorium
– Period of exploration
• Importance in contemporary society?
• What are some of the grounds of identity?
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Gender
Ethnicity/culture
Age group
Vocation
Political ideology
Religious/moral values
• What is gender identity?
– Function of gender roles
• Adolescence – adulthood
– Gender intensification
• Social/cultural pressures
• Peer pressures
• Parental pressures
• Biological pressures
• What is ethnic identity?
– Identification
• Physical/psychological characteristics
• Cultural practices/beliefs
– Racial socialization
• Majority vs. minority status
• Dislocation from native lands
• Cultural heritage
– Positive vs. negative identity
• Assimilation vs. marginality
• Bi-culturalism
• Vocational identity
– Aspect of identity associated with career.
• Being a lawyer
• Being a janitor
• Religious identity
– Aspect of identity associated with religious belief system.
• Being a Christian or Buddhist
• Being an atheist
• Age identity
– Aspects of identity associated with age group.
• Being a teenager
• Being an elderly person
Identity and stereotypes
• Identities commonly incorporate/activate
stereotypes
– Common characteristics associated with
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Being female
Being Native American
Being a plumber
Being a liberal
• Some characteristics positive, others negative.
• Stereotype activation makes these characteristics
salient.
– This can have incredibly powerful effects on behavior.
• Gender and ethnicity stereotypes
– Influence on academic performance
• When gender made salient
– Females under-perform on math exams
• When ethnicity made salient
– Blacks under-perform on academic tests
– Whites over-perform on academic tests
– Can be activated by something as simple as asking
ethnicity on demographic form!
Effect of Recording Race (Prime for Race)
10
9
Mean Items Correct
8
7
6
Black
White
5
4
3
2
1
0
Race Prime
No Race Prime
Presence of Race Prime
Effect of Stereotype Threat on Performance
12
10
Mean Items Correct
8
Black
6
White
4
2
0
Diagnostic
Non-Diagnostic
Stereotype Threat Condition
• Clash of multiple identities
• Asian females
– Baseline math performance
– When gender made salient, perform less well
– When ethnicity made salient, perform better
Percent of Items Answered Correctly
Stereotype Threat and Math Performance
60
50
40
30
20
10
0
Female
Control
Primed Identity
Asian
Other effects
• When primed with racial stereotypes people were more likely
to perceive a power tool as a gun.
• People primed with elderly stereotype will perceive hills to be
steeper and distances longer.
• People primed with stereotype of obesity perceived people to
be less intelligent, more lazy.
• Priming with gender influences perception of artistic pieces
and writing.
• Priming of identity stereotypes facilitate specific
interpretations of behavior.
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Positive identity stereotypes create “uplift”
Negative identity stereotypes create “threat”
A person can have a mixture of both in their identity.
Subtle and powerful influence of our identity on our
perception, attitudes, and behaviors.