Adolescence

1. Adolescence Psyc311 Developmental Dr. Wright

2. 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.

3. time periods of adolescent • Adolescence is a unique developmental period • it keeps changing! • Earlyadolescence – 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…)

4. 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

5. Tanner Stages

6. Tanner Stages

7. 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

10. 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

11. 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

13. The hormonal changes brought on by puberty can affect the adolescent’s behavior in at least three ways.

14. 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

15. 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?

16. moods

17. timing - individual factors • Genetic factors • Timing and tempo • Environmental factors • Nutrition • Body weight • Exposure to hormones/chemicals • Family conflict • Stepfathers

18. 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

21. 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

22. 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

23. the second wave…. • Longitudinal fMRI studies reveal: • Period of rapid synaptogenesisandpruning • Increased myelination (back to front) • Opportunity for massive cognitive growth and learning • Shift into Piaget’sformal operations

24. Among the most important changes to take place in the adolescence brain are those in the prefrontal cortexand limbic system.

25. (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

26. 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

27. 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

28. 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

29. conduct problems Adolescents whose prefrontal cortical development is less mature than normal are even more likely to have conduct problems. Populations most at risk?

30. teen pregnancy

31. 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

33. 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

34. Why is teenage pregnancy higher in the US?

35. consequences • SES factors • 50% of pregnancies occur in most impoverished populations • 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

36. consequences • Should we be concerned about this? • For teenage parents • mother in particular • For baby • For families • For community • Methods of prevention?

38. 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

40. 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?

41. adolescent substance abusers Compared to experimenters: more antisocial, impulsive acts start earlier more likely to be affected by genetic and environmental factors low SES family drug use family difficulties physical, sexual abuse poor school performance

43. 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?

44. 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

45. 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

46. cognitive changes • Importance of conceptual structureof 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

47. 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

48. 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

49. adolescent egocentrism • Increased introspection, self-consciousness, rationalization • Responsible for adolescent version of egocentrism. • Imaginary audience • Personal fable • Importance of personal individuality

50. Crisis never begins: diffusion • Crisis begins –> ends with foreclosure • Crisis begins –> ends with achievement • Psychosocial moratorium • Period of exploration • Importance in contemporary society?