PHYSICAL AND COGNITIVE DEVELOPMENT IN ADOLESCENCE

CHAPTER 11

Adolescence a Definition

Adolescence is the developmental stage that spans the period from the end of childhood to the beginning of adulthood.

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Adolescence a Genesis

•The concept of adolescence did not exist until psychologist G. Stanley Hall first wrote about it in his book by that name in 1904.

– He portrayed this stage in life as one of “storm and stress,” the inevitable result of biological changes

– Anna Freud (1958), daughter of Sigmund Freud, considered a stormy adolescence a necessary part of normal development.

•Hall and Freud were wrong.AdditionalMaterial

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Adolescence a Genesis

•Compelling evidence now suggests that adolescence is not typically stormy and difficult•Adolescence poses

– a great risk to healthy development for about one-fourth of teenagers

– healthy development for at least one-half of them

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PHYSICAL MATURATION

Physical Manifestations of Puberty

Growth during Adolescence: The Rapid Pace of Physical and Sexual Maturation

Adolescent growth spurtboys grow 4.1 inches a year and girls 3.5 inches a year. •Weight increase•Skeletal changes•Muscle changes•Males lose subcutaneous fat •Male pain perception changes

•Accelerated growth spurt• Extremities first (head, hands, feet) • arms and legs • torso and shoulder growth

•Asynchronicity in growth AdditionalMaterial

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Growth Pattern

What is a secular trend?

• Earlier start of puberty is example of significant secular trend– Pattern of change occurring over several generations– Trends occur when physical characteristic changes

over course of several generations– Result of better nutrition over centuries

Puberty in Girls

Begins earlier for girls than for boys•Girls start puberty at around age 11 or 12 (7 to 16)•and boys begin at around age 13 or 14•Wide variations among individuals

Influences•Nutrition•Health•Environmental stress•Environmental factors bisphenol A (BPA), birth control hormones, etc.

Onset of Menarche

• Varies in different parts of world

• Begins later in poorer, developing countries

• Influenced by proportion of fat to muscle in body

• Related to environmental stress

• Environmental Stuff

Puberty in Boys

• External genatilia begin to grow at accelerated rate around age 12 and reach adult size about 3 or 4 years later

• Enlargement of prostate gland and seminal vesicles

• Spermarche around age 13– Unreliable measure of sexual maturity

Primary Sex Characteristics

Further development of sex glands•Testes in males

•Ovaries in females

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Secondary Sex Characteristics A Definition

Secondary sex characteristics are those physical characteristics not directly involved in reproduction that distinguish the mature male from the mature female.

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Secondary Sex Characteristics

•Growth of hair:– Pubic– Facial– Body

•Changes to external genitalia

Body Image: Reaction to Physical Changes in Adolescence

Some of the changes of adolescence do not show up in physical changes, but carry psychological weight•Some changes are more public than others

•Some teenagers entering puberty are embarrassed by these changes

•Girls are frequently unhappy about their changing bodies

Sexual Maturation

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Puberty - Timing

• The timing of puberty can have importantpsychological consequences• coming at a time when a sense of security isgained from being like other members of the peer

group.

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Consequences of Early and Late Maturation

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Early-Maturing Boys

• Early maturation bestows – important physical & emotional advantages – enhanced status in the peer group

• taller and stronger than their classmates• have an advantage in sports • capture admiring glances from the girls• are likely to have a positive body image

– feel confident, secure, independent, and happy– be more successful academically

• viewed more favorably by adults. • perceived as being more attractive • given more responsibility and freedom

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The Consequences of Early and Late Maturation

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Early-Maturing Girls• Social advantages and disadvantages of early and late

maturation are less clear for girls.• Early-maturing girls feel more self-conscious about their

developing bodies and their size. • Have to deal with the sexual advances of older boys

before they are emotionally or psychologically mature• Have earlier sexual experiences and more unwanted

pregnancies than late-maturing girls• Are more likely to be exposed to alcohol and drug use• Tend to perform less well academically than age mates• By later adolescence, when peers have caught up,

– early maturers tend to be shorter and heavier than later maturers

– more likely to be unhappy with their physical appearance

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The Consequences of Early and Late Maturation

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Late-Maturing Boys

• Judged as less attractive by peers and adults• at a disadvantage socially and athletically. • are self-conscious about their size • are self-conscious about lack of manliness

– a deep voice – a developing beard.

• are often teased by their peers • treated like “kids.”

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The Consequences of Early and Late Maturation

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Late-Maturing Girls

• Often experience considerable stress when they fail to develop physically along with their peers.

• Compensation for the late-maturing girl: – As an adult she is likely to be taller and slimmer

than her early-maturing age mates.

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Nutrition, Food, and Eating Disorders: Fueling the Growth of Adolescence

Fueling the Growth of Adolescence

For most adolescents, the major nutritional issue is ensuring the consumption of a sufficient balance of appropriate foods•Rapid physical growth of adolescence is fueled by an increase in food consumption

•Particularly during the growth spurt, adolescents eat substantial quantities of food, increasing their intake of calories rather dramatically

– During the teenage years, the average girl requires some 2,200 calories a day

– The average boy requires 2,800

•Several key nutrients are essential, including, in particular, calcium and iron

Nutritional Problems in Adolescence

Poor eating habits•High consumption of junk food/sugar/fats•Large portion sizes•Lack of variety

Related health concerns•Obesity•Osteoporosis•Diabetes•Heart disease

Some adolescences have problemsMany just need additional caloriesHigh quality food simply not ‘handy’.

Pubertal Changes and Eating DisordersMostly due to inactivity!

• Ratio of body fat to muscle increases

• Basal metabolism rate decreases

• Overall physical appearance changes

• 20% overweight; 5% obese; 15% seriously overweight

Pubertal Changes and Eating Disorders

Anorexia Nervosa and Bulimia

Definitions•Anorexia=starvation to maintain low weight•Bulimia=binge and purge eating

– 1% anorexic and 3% bulimic– Higher incidence among females

•Disordered eating and body dissatisfaction reported across socioeconomic lines

Brain Development and Thought: Paving the Way for Cognitive Growth

A No Brainer?????

• Brain changes– Size– Maturity

• Growth spurts– Different part of brain– Different times

Use It or Lose It

• Brain produces oversupply of gray matter during adolescence which is later pruned back at rate of one to two percent per year

• Myelination increases and continues to make transmission of neural messages more efficient

How is this related to adolescent impulse control?

• Prefrontal cortex provides for impulse control

• Adolescence prefrontal cortex is biologically immature = ability to inhibit impulses is not fully developed

Figure 11-5 Pruning Gray MatterThis three-dimensional view of the brain shows areas of gray matter that are pruned from the brain between adolescence and adulthood. (Source: Sowell et al., 1999.)

Yawning of the Age of Adolescence

Sleep Deprivation•Adolescents go to bed later and get up earlier•Caused by societal demands•Adolescence biological clock shifts - Bed late arise late

• Sleep deprivation takes its toll– Lower grades– More depressed– Greater difficulty controlling their moods– Greater risk for auto accidents

COGNITIVE DEVELOPMENT AND SCHOOLING

Cognitive Development

Approaches•Piaget

•Information processing

•Adolescent egocentrism

Piagetian Perspective

• Formal Operational Stage• The “Final Stage”

• Fundamentally different than child thinking• Incorporates new, more advanced, and more adaptive

form of reasoning

• Utilized in variety of settings and situations

Piagetian Stages Related to Youth Development

Formal operations•11+ years

•Development of abstract and hypothetical reasoning

•Development of propositional logic

•Cultural differences in use•Many adults never achieve FOT•But sometimes occurs in mid-life

Developmental of Formal Operations

Emergent•Early adolescence•Variable usage depends on conditions surrounding assessment

Established•Late adolescence•Consolidated and integrated into general approach to reasoning

Consequences of Adolescents’ Use of Formal Operations

Ability to reason abstractly, embodied in their use of formal operations, leads to a change in their everyday behavior•Questioning parents and authority figures

•Exhibiting greater idealism and impatience with imperfections

•Experiencing indecision

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Abstract Thinking Advantages

• With full operational thinking, adolescents can attack problems by systematically testing hypotheses and drawing conclusions through deductive reasoning.

• When HS students develop FOT they can – understand algebra – decipher analogies and metaphors in English lit.

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Abstract Thinking Abilities

• With formal operations comes the ability to– explore the world of ideas– to look at religion and moral values in a new light– to consider different philosophies and political

ideas• FOT enables adolescents to think hypothetically• They can think of what might be. • They begin to conceive of “perfect” solutions to the

world’s problems.

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FOT not Automatic

• FOT does not develop automatically• may be absent in some primitive cultures• rare to find HS or college students in the US who can

solve Piagetian formal operations tasks w/o training.

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FOT or Concrete Thinking?

• One longitudinal study of American adolescents and adults concluded that only 30% of those studied attained formal operations

• Many people fail to show formal operational thinking

• Those who do attain it usually apply it only in those areas in which they are most proficient

• Some studies suggest that even very intelligent, well-educated adults think best when thinking concretely

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Information Processing Perspectives: Gradual Transformations in Abilities

• Changes in adolescents’ cognitive abilities are evidence of gradual transformations in the capacity to take in, use, and store information

• Number of progressive changes occur in the ways people organize their thinking about the world, develop strategies for dealing with new situations, sort facts, and achieve advances in memory capacity and perceptual abilities

• Incorporates same techniques to understanding human reasoning that computer scientists employ in writing programs

Changes in Information Processing

• Gains during adolescence help to explain developmental differences in abstract, multidimensional, and hypothetical thinking

• Store of knowledge increases as the amount of material to which they are exposed grows and their memory capacity enlarges

• Fails to explain qualitative differences

Egocentrism in Thinking: Adolescents’ Self-Absorption

• New abilities make adolescents particularly introspective and self-conscious

• These hallmarks of may produce a high degree of egocentrism

• Adolescent egocentrism is a state of self-absorption in which the world is viewed as focused on oneself– Imaginary audience– Personal fables

– Everyone’s lookin’ at me!

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Personal Fable:

An exaggerated sense of personal uniqueness and indestructibility, which may be the basis for adolescent risk taking.

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Adolescent Egocentrism: the Personal Fable

Adolescents cannot fathom that anyone has ever felt as deeply as they feel or loved as they love.

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Adolescent Egocentrism: Disputing Elkind’s Views

• Quadrel and others (1993) dispute Elkind’s explanation for adolescent risk taking.

• They found – both high-risk adolescents (from group homes

or juvenile centers) and middle-class, low-risk adolescents actually perceived themselves as more likely to experience certain negative events—injury in an auto accident, alcohol dependency, mugging, and so forth—than did adults.

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Adolescent Egocentrism: Disputing Elkind’s Views

• Adolescents are willing to engage in high-risk behaviors in spite of the risks involved– perhaps because of peer pressure– Perhaps because the pleasure outweighs the risk.

• According to Bjorklund & Green, risk taking may even have some positive consequences.– may enable adolescents to “experiment with new

ideas and new tasks and generally behave more independently.

– Many of these experiences will be adaptive for adult life and for making the transition to adulthood”

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Adolescent Egocentrism: The whole enchilada

At Center Stage, Unique, and Indestructible• David Elkind (1967, 1974) claims that the early

teenage years are marked by adolescent egocentrism, which takes two forms– the imaginary audience – the personal fable.

• Do you remember, as a teenager, picturing how your friends would react to the way you looked when you made your grand entrance at a big party? Additional

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Adolescent Egocentrism: Imaginary Audience

An imaginary audience of admirers (or critics) that adolescents conjure up exists only in their imagination; “but in the young person’s mind, he/she is always on stage”

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Thinking about Thinking…

Metacognition improves during adolescence• Thinks about own thoughts self-consciousness

• Monitors own learning processes more efficiently

• Paces own studying

School Performance

True or False?

Grades awarded to high school students have shifted upward in the last decade.

Grade inflation occurred in colleges too.

Students Around the World

Figure 11-6 U.S. 15-Year-Old PerformanceCompared with Other CountriesWhen compared to the academic performance of students across the world, U.S. students perform at below-average levels.

(Source: Based on National Governors Association, 2008.)

But, somehow, U.S. workers have highest levels of productivity, innovation, creativity,Inventions, scientific advances and on and on.

Adolescent Media Usage

Kaiser Family Foundation survey•Young people spend an average of 6.5 hours a day with media•Around a quarter of the time they are using more than one form of medium simultaneously, they are actually being exposed to the equivalent of 8.5 hours per day•Some teenagers send nearly 30,000 texts a month

See Figure 11-7 for additional information on teenagers, cell phones, and texting

Dropping Out of School

Adolescents leave school for variety of reasons•Males are more likely to drop out of school than females

•Hispanics and African American students are more likely to leave high school before graduating than others

•Not all minority groups show higher dropout rates: Asians drop out at a lower rate than Caucasians

•Poverty plays large role in higher dropout rate•Local culture is probably driving factor

THREATS TO ADOLESCENTS’ WELL-BEING

Adolescent Drug Use

• One in 15 high school seniors smokes marijuana on a daily or near-daily basis

• Marijuana usage has increased over the last few years

• Daily marijuana use is at a 30-year high for high school seniors

How Common is Illegal Drug Use during Adolescence?

Figure 11-8 Downward TrendAccording to an annual survey, the proportion of students reporting marijuana use over the past 12 months has decreased since 1999.

(Source: Johnston et al., 2011.)

Why Do Adolescents Use Drugs?

• Pleasurable experience • Escape• Peer pressure• Enhanced academic performance

• Book fails to mention self medication

Why do adolescents start to drink?

• Genetics

• Way of proving themselves

• Release of inhibitions and tension and reduction of stress

• False consensus effect

• Local culture – Upper Midwest

Sexually Transmitted Infections (STIs) Among Adolescents

Vast majority of infection Caused by female contact withadult males.