1. Physical and Cognitive Development in Adolescence
Chapter 11
Physical and Cognitive Development in Adolescence
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3. Nature of Adolescence Thoughts are more abstract & idealistic.
Biological changes trigger a heightened interest in body image.
Generally, adolescents have positive self-concepts & good relationships with others.
Genetic, biological, environmental, & social factors interact in teen development.
Continuity/discontinuity both play a role.
Dating begins.
Relationships with parents take a different form.
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5. Puberty
Definition of Puberty
Puberty is a period of rapid physical maturation involving hormonal & bodily changes that occur primarily during early adolescence.
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6. Individual Variation in Puberty
Puberty determinants include:
Nutrition
Health
Heredity
Body mass
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7. Individual Variation in Puberty
Boys – pubertal sequence begins between ages yrs.
Girls – normal range is between yrs. (onset of menarche, or first menstrual period).
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8. Puberty
What are Hormones?
Powerful chemical substances secreted by the endocrine glands & carried through the body by the bloodstream
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9. Puberty
Endocrine System
Hypothalamus – a structure in the higher portion of the brain that monitors eating, drinking, & sex
Pituitary gland – an endocrine gland that controls growth & regulates other glands
Gonads – the sex glands (testes in males, ovaries in females)
Gonadotropins – hormones that stimulate the testes or ovaries
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10. Puberty
Hormonal Changes
Puberty involves the interaction of the endocrine system’s hypothalamus, pituitary gland, & gonads.
The pituitary gland also interacts with the thyroid gland to produce growth & skeletal maturation.
Concentrations of certain hormones (testosterone, estradiol) increase dramatically during adolescence.
Hormones contribute to both physical & psychological development.
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11. Puberty
Height and Weight
Growth spurt – occurs about 2 years earlier for girls.
Mean age of growth spurts – age 9 for girls; age 11 for boys.
Peak rate of pubertal change – age 11.5 for girls; age 13.5 for boys.
Height increases – about 9 cm per year for girls; about 10.6 cm for boys.
Weight increases follow a similar timetable as height.
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12. Sexual Maturation in Boys
Puberty
Sexual Maturation in Boys
Increase in penis & testicle size
Straight pubic hair appears
Minor voice change
Growth of facial hair
First ejaculation
Appearance of kinky pubic hair
Onset of maximum growth
Growth of hair in armpits
More detectable voice change
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13. Sexual Maturation in Girls
Puberty
Sexual Maturation in Girls
First menstruation comes rather late in puberty
Menstrual cycles are often highly irregular
Some girls aren’t fertile until 2 years later.
Breasts are fully rounded by the end of puberty
Breasts enlarge
Pubic hair appears
Hair appears in the armpits
Growth in height
Hips become wider than shoulders
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14. Body Image Preoccupation with body image occurs in adolescence.
Puberty
Body Image
Preoccupation with body image occurs in adolescence.
Wright (1989) found adolescents are more dissatisfied with their bodies during puberty than in late adolescence.
Brooks-Gunn & Paikoff (1993) found girls are less happy with their bodies & have more negative body images than boys throughout puberty.
Gross (1994) determined that during puberty, girls often become dissatisfied with their bodies due to the increase in body fat, while boys become more satisfied due to the increase in muscle mass.
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15. Early and Late Maturation in Boys
Puberty
Early and Late Maturation in Boys
Simmons & Blyth’s (1987) research confirms that during adolescence, it is advantageous to be an early-maturing rather than late-maturing boy.
Early maturing boys appear to perceive themselves more positively & have more successful peer relations than their late-maturing counterparts.
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16. Early and Late Maturation in Girls
Puberty
Early and Late Maturation in Girls
Simmons & Blyth (1987) recent findings suggest that early-maturing girls experience more problems in school.
They also experience more independence & popularity with boys.
In 6th grade, early-maturing girls show greater satisfaction with their figures, but by 10th grade, late-maturing girls are more satisfied.
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18. Adolescent Sexuality
Adolescent Sexuality
Adolescence is a time of sexual exploration & experimentation.
Adolescence is a bridge between the asexual child & the sexual adult.
Sexual development & interest are normal aspects of adolescent development.
The majority of adolescents have healthy sexual attitudes & engage in sexual practices that will not compromise their development.
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19. Adolescent Sexuality
Adolescent Sexuality
The World Health Organization defines sexual health as:
the integration of the physical, emotional, intellectual & social aspects of sexual being in ways that are positively enriching & that enhance personality, communication & love.
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20. Developing a Sexual Identity
Adolescent Sexuality
Developing a Sexual Identity
Sexual identity involves:
an indication of sexual orientation
activities
interests
styles of behaviour
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21. The Progression of Adolescent Sexual Behaviour
Adolescent Sexuality
The Progression of Adolescent Sexual Behaviour
8 in 10 girls are virgins at age 15.
7 in 10 boys are virgins at age 15.
Adolescents engage in a consistent progression of sexual behaviours:
Necking
Petting
Intercourse/Oral sex
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22. Risk Factors and Sexual Problems
Adolescent Sexuality
Risk Factors and Sexual Problems
Adolescents who engage in sex before age 16 are the least effective users of contraception.
They are also at risk for unintended pregnancy and sexually transmitted diseases.
Early sexuality is also linked with excessive drinking and drug use.
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23. Contraceptive Use Two kinds of risks that youth encounter:
Adolescent Sexuality
Contraceptive Use
Two kinds of risks that youth encounter:
unintended/unwanted pregnancy
sexually transmitted diseases
Both of these risks can be reduced significantly if contraception is used.
Adolescents are increasing contraceptive use.
Younger adolescents are less likely to use them.
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24. Sexually Transmitted Infections and Diseases
Adolescent Sexuality
Sexually Transmitted Infections and Diseases
Sexually transmitted diseases (STDs) are contracted primarily through sexual contact, which is not limited to sexual intercourse. Oral-genital and anal-genital contact also can be involved in STDs.
Chlamydia and gonorrhea are more common among adolescents than young adults.
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25. Adolescent Sexuality
Adolescent Pregnancy
Each year, more than 40,000 teenage pregnancies occur in Canada.
The teen pregnancy rate did decline slightly in the 1990s.
Most adolescent pregnancies are unplanned.
Regional differences exist across Canada.
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26. Consequences of Adolescent Pregnancy
Adolescent Sexuality
Consequences of Adolescent Pregnancy
Adolescent pregnancy creates health risks for both the offspring & the mother.
Adolescent mothers often drop out of school.
Infants born to teen mothers are more likely to have:
low birthweights
neurological problems
childhood illness
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27. Reducing Adolescent Pregnancy
Adolescent Sexuality
Reducing Adolescent Pregnancy
Sex education and family planning
Access to contraceptive methods
The life-options approach
Broad community involvement and support
Abstinence, especially for young adolescents
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29. Adolescent Health Problems and Wellness
Teen Depression
Depression is defined as experiencing over a prolonged period of time a range of symptoms including fatigue, irritability, inability to make decisions, sleeping problems, lack of interest in daily activities, and suicidal thoughts.
Boys were half as likely to suffer from depression.
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30. Higher Rates of Depression in Females
Adolescent Health Problems and Wellness
Higher Rates of Depression in Females
Females tend to internalize emotions.
Females tend to ruminate in their depressed mood and amplify it.
Females’ self-image, especially their body images, are more negative than those of males.
Females face more discrimination than do males.
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31. Substance Use and Addiction
Adolescent Health Problems and Wellness
Substance Use and Addiction
Dopamine in the Brain
Alcohol
Cigarette Smoking
Gambling
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32. Adolescent Health Problems and Wellness
Dopamine in the Brain
Dopamine is one of the key brain chemicals that carry & influence messages between nerve cells.
It is heavily involved with pleasure – reward circuit of the brain.
All addictive drugs artificially increase the amount of dopamine in the reward centres of the inner brain by either jump-starting its release or prolonging its stay.
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33. Adolescent Health Problems and Wellness
Alcohol
Alcohol is the drug most widely used by adolescents in our society.
Since 1980, alcohol related deaths among teenage drivers has dropped by 61% in Canada.
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34. Cigarette Smoking Begins primarily during childhood & adolescence.
Adolescent Health Problems and Wellness
Cigarette Smoking
Begins primarily during childhood & adolescence.
A study found that once young adolescents begin smoking, the addictive properties of nicotine make it extremely difficult for them to stop.
The early age of onset of smoking is more important in predicting genetic damage than how much individuals smoke.
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35. Adolescent Health Problems and Wellness
Gambling
Gambling is a hidden addiction because it has no visible signals.
About 80% of Canadians gamble.
The number of pathological gamblers in Canada may be as high as 1.2 million.
Gambling has become increasingly popular with high school students.
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36. Risk, Vulnerability, and the Role of Parents and Peers
Adolescent Health Problems and Wellness
Risk, Vulnerability, and the Role of Parents and Peers
Drug use in childhood or early adolescence has more detrimental long-term effects on the development of responsible, competent behaviour than when drug use occurs in late adolescence.
Positive relationships with parents & others are important in reducing adolescents’ drug use.
Adolescents are most likely to take drugs when both of their parents take drugs & when their peers take drugs.
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37. Eating Disorders Anorexia Nervosa Bulimia Nervosa
Adolescent Health Problems and Wellness
Eating Disorders
Anorexia Nervosa
Bulimia Nervosa
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38. Adolescent Health Problems and Wellness
Anorexia Nervosa
An eating disorder that involves the relentless pursuit of thinness through starvation; can lead to death.
Anorexics often weigh less than 85% of what is considered normal.
Intense fear of gaining weight does not dissipate with weight loss.
Distorted perception of body shape drives constant weighing & starving.
Most are White adolescent or young adult females from well-educated, middle & upper income families.
High standards & stress at not reaching them are factors.
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39. Adolescent Health Problems and Wellness
Bulimia Nervosa
An eating disorder in which the individual consistently follows a binge-and-purge eating pattern.
Purging is accomplished through self-inducing vomiting or use of a laxative.
Most bulimics are females in the teens to early twenties.
Most bulimics are preoccupied with food, have a strong fear of becoming overweight, & are depressed or anxious.
Unlike anorexia, bingeing & purging occurs within a normal weight range & is difficult to detect.
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40. Leading Causes of Death in Adolescence
Adolescent Health Problems and Wellness
Leading Causes of Death in Adolescence
Accidents – most involve automobiles, and are the result of risky driving habits and driving under the influence of alcohol or drugs.
Suicide – accounts for 6% of the deaths in the 10–14 age group, and 12% of deaths in the 15 – 19 age group.
Alcohol and Illicit Drug Use – being under the influence of alcohol or drugs may result in riskier behaviour, which in turn results in more accident fatalities.
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42. Piaget’s Theory Adolescent thought is at the formal operational stage.
Adolescent Cognition
Piaget’s Theory
Adolescent thought is at the formal operational stage.
Thought is more abstract, characterized by:
verbal problem-solving ability
increased tendency to think about thought itself
idealism and possibilities
more logical
hypothetical-deductive reasoning
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43. Hypothetical-Deductive Reasoning
Adolescent Cognition
Hypothetical-Deductive Reasoning
Piaget’s formal operational - adolescents have the cognitive ability to develop hypotheses, or best guesses, about ways to solve problems, such as an algebraic equation. They then systematically deduce, or conclude, which is the best path to follow in solving the equation.
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44. Adolescent Egocentrism
Adolescent Cognition
Adolescent Egocentrism
Egocentrism is the heightened self-consciousness of adolescents, reflected in their belief that others are as interested in them as they themselves are, & in their sense of personal uniqueness.
Dissected into two types of social thinking:
imaginary audience
personal fable
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45. Adolescent Cognition
Imaginary Audience
Imaginary Audience refers to the heightened self-consciousness of adolescents, reflected in their belief that others are as interested in them as they themselves are.
Involves attention-getting behaviour—the attempt to be noticed, visible, & the sense of being “on stage.”
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46. Adolescent Cognition
Personal Fable
Personal fable is the part of adolescent egocentrism involving an adolescent’s sense of uniqueness & invulnerability.
Adolescents feel that no one can understand how they really feel.
Personal fables frequently show up in adolescent diaries.
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47. Information Processing
Adolescent Cognition
Information Processing
Decision Making
Critical Thinking
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48. Adolescent Cognition
Decision Making
Increased decision making opportunities occur in adolescence.
Compared with children, young adolescents are more likely to generate options, examine a situation from a variety of perspectives, anticipate the consequences of decisions, & consider the credibility of sources.
Parents should involve adolescents in appropriate decision-making activities.
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49. Adolescent Cognition
Critical Thinking
A solid basis of fundamental skills is necessary for the development of critical thinking skills.
Recent studies have shown critical thinking increases with age, but still only occurs less than half the time with eleventh grade students.
Cognitive changes that allow improved critical thinking are:
increased speed and capacity of information processing
more breadth of content knowledge in a variety of areas
increased ability to construct new knowledge combinations
a greater range and more spontaneous use of strategies
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50. Adolescent Cognition
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51. Education Effective Schools High School Dropouts Adolescent Cognition
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52. Adolescent Cognition
Effective Schools
Effective schools offer more than the “3 Rs”; they are accountable and responsible to public scrutiny.
Trademarks of effective schools:
Effective leadership
Clear academic goals
A safe and orderly climate
Expectation of minimum mastery of skills
Testing for program evaluation and redirection
Parental involvement
Collegiality
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53. Adolescent Cognition
Hidden Curriculum
The “hidden curriculum” is conveyed by the moral atmosphere that is a part of every school.
The moral atmosphere is created by school and classroom rules, the moral orientation of teachers and school administrators, and text materials.
Teachers serve as models of ethical and unethical behaviour.
Through rules and regulations, school administrations infuse a school with a value system.
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54. Adolescent Cognition
High School Dropouts
In the last 50 years the school completion rate in Canada has increased from 50% to 80%.
Almost 50% of those who leave school return by age 20 to complete their high school education.
Aboriginal youth have a disproportionately high rate of leaving school – approximately 70%.
Nova Scotia reports the lowest provincial dropout rate of 13%.
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55. Who Leaves School? Characteristics of people who leave school:
Adolescent Cognition
Who Leaves School?
Characteristics of people who leave school:
Are disabled
Have dependants
Have fathers that didn’t complete high school
Have changed schools a number to times
Live with friends or alone rather than with families
Work
Are male
Live common law or have been separated or divorced
Have parents or friends who do not consider school important
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