Chapter 11: Human Development Across the Life Span

Progress Before Birth: Prenatal Development

•

3 phases

–

germinal stage

= first 2 weeks • conception, implantation, formation of placenta –

placenta is a structure that allows oxygen and nutrients to pass into the fetus from the mother’s bloodstream and bodily wastes to pass out to the mother

Progress Before Birth: Prenatal Development

–

embryonic stage

= 2 weeks – 2 months • formation of vital organs and systems (

such as the heart, spine, and brain emerge)

•

time of great vulnerability

Progress Before Birth: Prenatal Development

–

fetal stage

= 2 months – birth • bodily growth continues, movement capability begins, brain cells multiply • age of viability:

between 22 and 26 weeks, the baby could survive if born prematurely

•

the muscles and bones begin to form

•

sex organs developing in the 3rd month

Figure 11.1 Overview of fetal development

Environmental Factors and Prenatal Development

•

Maternal nutrition

–

malnutrition has been shown to have negative effects for many years after birth. Research links maternal malnutrition to vulnerability, schizophrenia, and other psychiatric disorders in adolescence and early adulthood

Environmental Factors and Prenatal Development

•

Maternal drug use

– Tobacco, alcohol, prescription, and recreational drugs:

linked to birth defects

– Fetal alcohol syndrome

causes of mental retardation

• • :

one of the leading Problems include microcephaly, heart defects, irritability, hyperactivity, and delayed mental and motor development also related to increased incidence of depression, suicide, and criminal behavior in adulthood

Environmental Factors and Prenatal Development

•

Maternal illness

– Rubella, syphilis, mumps, genital herpes, AIDS, severe influenza •

the nature of the damage depends on when the mother contracts the illness

– Prenatal health care:

associated with higher survival rates and reduced prematurity

The Childhood Years: Motor Development

• •

Motor development refers to the progression of muscular coordination required for physical activities

Basic Principles

–

Cephalocaudal trend

– head to foot –

Proximodistal trend

– center-outward

The Childhood Years: Motor Development

•

Motor development depends in part on physical growth, as well as on the process of maturation, and the infant’s ongoing exploration of the world.

–

Maturation

blueprint – gradual unfolding of genetic –

Developmental norms

:

age at which individuals display various behaviors and abilities

• median age (

useful benchmarks only)

– Cultural variations:

in motor development indicate the importance of experience on the development of motor skills

Easy and Difficult Babies: Differences in Temperament

• Longitudinal studies:

observe one group of participants repeatedly over time

–

more sensitive to developmental influences

• cross-sectional designs:

compare groups of participants of differing age at a single point in time

–

easier, quicker, and cheaper

• Temperament

: an individual’s characteristic mood, activity level, and emotional reactivity

Easy and Difficult Babies: Differences in Temperament

•

Thomas, Chess, and Birch (1970)

–

temperamental individuality is established by about 2-3 months of age, it was stable over time

– 3 basic temperamental styles •

easy

– 40%: happy, regular in sleep and

eating, adaptable, and not readily upset

• • •

slow-to-warm-up

– 15%: happy, regular in

sleep and eating, adaptable, and not readily upset, with moderate reactivity

difficult

– 10%: glum, erratic in sleep and

eating, resistant to change, and relatively irritable

mixed – 35%

Easy and Difficult Babies: Differences in Temperament

• •

Thomas and colleagues used parent reports, Jerome Kagan and colleagues relied on direct observations

Kagan & Snidman (1991)

– Inhibited:

shyness, timidity, and wariness of the unfamiliar

– uninhibited temperament:

less restraint with regard to the unfamiliar and little trepidation

• •

inhibited – 15 - 20% uninhibited – 25 - 30%

– stable over time, genetically based

Figure 11.6 Longitudinal versus cross-sectional research

Early Emotional Development: Attachment

• Harry Harlow – Made 2 ‘monkeys’ – Wanted to see if feeding was the key determinant in infant attachment – Found that the real monkey’s went to the comfortable ‘monkey’ when scared – Also found that babies are programmed to emit behavior that triggers an affectionate, protective response from adults

Early Emotional Development: Attachment

• •

Attachment refers to the close, emotional bonds of affection that develop between infants and their caregivers

Separation anxiety: emotional distress seen in many infants

when they are separated from people with whom they have formed an attachment

–

Ainsworth (1979)

– The

strange situation

and patterns of attachment •

Secure:

playing and exploring comfortably when mom is present, becoming visibly upset when she leaves, and calming quickly upon her return.

• Anxious-ambivalent: show anxiety even when mom is

near and protest excessively when she leaves, but are not particularly comforted when she returns

• Avoidant: some babies sought little contact with their

mothers and were not distressed when she left

Early Emotional Development: Attachment

•

Developing secure attachment

– Bonding at birth:

first few hours after birth does not appear to be crucial to secure attachment

– Daycare:

recent research by the NICHD indicates that day care is not harmful to children’s attachment relationships, and there is evidence that there may be beneficial effects of day care on social development in children from deprived backgrounds .

– Cultural factors: vary across cultures

Early Emotional Development: Attachment

•

Evolutionary perspectives on attachment:

– –

John Bowlby,assumed attachment to be a function of natural selection, with infants programmed to emit behaviors that trigger affectionate, protective responses in adults.

Jay Belsky (1999) asserts that children have been programmed by evolution to respond to sensitive or insensitive care with different attachment patterns.

Stage Theories of Development: Personality

•

Stage theories

, three components – progress through stages in order – progress through stages related to age – major discontinuities in development

Figure 11.10 Stage theories of development

Stage Theories of Development: Personality

•

Erik Erikson (1963)

– Eight stages spanning the lifespan –

Psychosocial crises

determining balance between opposing polarities in personality –

there is a specific psychosocial crisis during each stage, the outcome of which determines the balance between opposing polarities in personality

Figure 11.11 Erikson’s stage theory

Stage Theories: Cognitive Development

•

Jean Piaget (1920s-1980s):

asserting that interaction with the environment and maturation gradually alter the way children think

–

Assimilation:

interpreting new experiences in terms of existing mental structures without changing them

–

Accommodation:

changing existing mental structures to explain new experiences

–

IPOD example…

Stage Theories: Cognitive Development

– 4 stages and major milestones •

Sensorimotor

– Object permanence

visible.

:

the recognition that objects continue to exist even when they are no longer

–

(birth to 2 years)

•

Preoperational

– Centration:

tendency to focus on just one feature of a problem

– Egocentrism:

the limited ability to share another’s viewpoint

– Irreversibility: can’t reverse an action –

(2-7 years)

Stage Theories: Cognitive Development

•

Concrete Operational

– Decentration:

able to focus on more than one feature of a problem simultaneously

– Reversibility:

mentally undoing an action

–

These new cognitive skills lead to conservation, or recognizing that amount of a substance does not change just because appearance is changed

– 7-11 years-old •

Formal Operational

–

marked by the ability to apply operations to abstract concepts such as justice, love, and free will

–

11- adulthood

Figure 11.12 Piaget’s stage theory

Figure 11.13 Piaget’s conservation task

Figure 11.14 The gradual mastery of conservation

Weaknesses of Piaget

• 1) might have underestimated the pace at which children progress • 2) Did not see individual development; there can be a mixing of stages as a child progresses (no clearly defined stage) • 3) Further research has shown that the sequence of stages is largely correct, but the timetable at which you progress varies across cultures (underestimated culture)

Vygotsky’s Sociocultural Theory

• Vygotsky (Russian 1920-30’s); died early in career – Emphasized how children’s cognitive abilities are fueled by social interactions (parents, teachers, peers) who can provide guidance • Both good and bad – Argued the mastery of language plays a central role in fostering cognitive development

Vygotsky’s Sociocultural Theory

• Cont.

– New Ideas: • Zone of Proximal Development: the difference between what a person can accomplish alone and with a more skilled ‘mentor’ • Scaffolding: adjusting the difficulty of a task as the learner progresses • Private Speech: children talk to themselves to work out strategies (Piaget discarded as egocentric), as the children age the speech becomes internal

Are some Cognitive Abilities Innate?

• Research was done on infants – Used Habituation: a gradual reduction of a response after an event is presented repeatedly – Dishabituation: a new stimulus elicits an increase in the strength of a habituated response • Ex: show infants same picture over and over (heart rate and respiration decrease)- Hab.

• new picture introduced (heart rate- respiration increase) Dishab.

Are some Cognitive Abilities Innate?

• Results – 3-4 mos. • Children understand that objects have solid boundaries • take continuous paths • Objects can’t pass through each other or opening smaller than the objects • Things roll down a slope, not up – 9-12 Mos.: Children can group things into categories

Are some Cognitive Abilities Innate?

• But can they add and subtract?

– Featured Study • What were the results?

Featured Study Result

• Researcher said the results pointed to the fact that 9 mos. Olds could add and subtract • Other psychologists argue that the findings do not show mathematic ability, but the ability to track groups… • So don’t feel bad if math is hard…

The Development of Moral Reasoning

•

Kohlberg (1976)

–

based on subjects’ responses to presented moral dilemmas

–

interested in a person’s reasoning, not necessarily their answer

–

Moral dilemmas

–Measured nature and progression of moral reasoning

The Development of Moral Reasoning

– 3 levels, each with 2 sublevels •

Preconventional: Children think in terms of external authority

•

Conventional: rules are necessary for maintaining social order

•

Postconventional: rules are worked out as a personal code of ethics

Figure 11.17 Kohlberg’s stage theory

Adolescence: Physiological Changes

• Pubescence: the two-year span preceding

puberty during which the changes leading to physical and sexual maturity take place

– Secondary sex characteristics:

physical features that distinguish one sex from the other but that are not essential for reproduction

Adolescence: Physiological Changes

• Puberty: the stage during which sexual

functions reach maturity, marking the beginning of adolescence

– Primary sex characteristics • Menarche:

the first occurrence of menstruation

• Sperm production:

spermarche

Adolescence: Physiological Changes

•

Maturation: early vs. late

• •

Puberty is occurring at younger ages explanations for this trend include improvements in nutrition and medical care; maybe family relationships

• Sex differences in effects of early maturation –

early maturing girls and late maturing boys having greater risk for psychological problems and social difficulties

•

10-15 for girls is typical, 11-16 for boys

Figure 11.19 Physical development at puberty

Adolescence: Neural Changes

• Increasing myelinization: –

“white matter” increases

• Synaptic pruning – The brain becomes more efficient • Changes in prefrontal cortex –

last area of the brain to mature fully. Some researchers have suggested that this is connected with the increase in risky behaviors during adolescence.

• Controls: planning, organization, and emotional control

The Search for Identity

• •

Erik Erikson (1968) Identity vs. Confusion

– Key challenge - forming a sense of identity

James Marcia (1988):

–

presence or absence of crisis and commitment during the identity formation stage can combine in various ways to produce four different identity statuses

–

Focused on adolescence, but said these can occur at anytime

–

They progress through the following order of maturity:

The Search for Identity

– 4 identity statuses (Marcia) • Identity Diffusion:

is a state of lack of direction and apathy

–Social and psychological problems • Foreclosure:

premature commitment to a role prescribed by one’s parents

–Anxiety, conformity, and not open to new ideas

The Search for Identity

Moratorium:

involves delaying commitment and engaging in experimentation with different roles

–Self-doubt and confusion • Identity Achievement:

arriving at a sense of self and direction after some consideration of alternative possibilities

–Higher self-esteem, security, conscientiousness, achievement motivation, intimacy

The Expanse of Adulthood

• Personality development:

marked by both stability and change

– Extraversion, neuroticism, and openness to experience decline – Agreeableness and conscientiousness increase –

Adults who move successfully through Erikson’s stages develop intimacy, generativity, and integrity.

The Expanse of Adulthood

• Social development –

Marriage: marital satisfaction indicate that when spouses have differing role expectations, adjustment to marriage is more difficult. Research also shows highest rates of marital satisfaction at the beginning and end of the family cycle

The Expanse of Adulthood

–

Parenthood: adjustment to parenthood proceeds more smoothly if unrealistic expectations are not held

–

parent-adolescent relations and the adjustment difficulties that parents may have when children leave home (empty nest syndrome) may not be as stressful as once believed

The Expanse of Adulthood

• Erikson’ View of Adulthood – Intimacy vs. Isolation • Early adulthood; empathy and openess vs shrewdness and manipulativeness – Generativity vs. Self-absorption • Middle adulthood; a concern for future generations vs. self-indulgent concerns – Integrity vs. Despair • Late adulthood; has my life meant anything

The Expanse of Adulthood

• • Career development:

tends to proceed through stages of exploration of careers, establishment of a career, maintenance, and decline.

• 40’s most productive decade • Physical changes: –

changes in appearance, neuron loss, sensory loss, and hormonal changes.

–

Research indicates that menopause is not as problematic as once thought.

The Expanse of Adulthood

• Alzheimer’s Disease

The Expanse of Adulthood

• Cognitive changes –

general mental ability remains fairly stable, with small declines in IQ after age 60

–

Fluid intelligence is more likely to decline with age

–

crystallized intelligence remains stable or increases

–

Mental speed declines in late adulthood, and memory losses have been reported in many studies. These are moderate and variable