Copyright © 2011 Pearson Education, Inc. All rights reserved. Copyright © 2011 Pearson Education, Inc. All rights reserved.
Psychology:
From Inquiry to Understanding 2/e
Chapter Ten
Human Development: How and Why We
Change
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Lecture Preview
Special considerations in development
The developing body: Physical and motor development
The developing mind: Cognitive development
The developing personality: Social and moral development
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Developmental Psychology
The study of how behavior changes over the life span
Several challenges arise when examining human development
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Post hoc Fallacy
Logical error where you assume that A causes B, just because B came after A
For example, all serial killers drink milk as babies, so milk causes people to be serial killers
Shy kids become engineers
Correlation vs. Causation problem (remember Chapter 2)
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Bidirectional Influences
Human development is almost always a two-way street
Children’s development influences their experiences, but their experiences also influence their development
E.g. Genain quadruplets
Children also change their environments by acting in ways that create changes in others’ behavior
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Cohort Effects
Sets of people who lived during one period can differ in some systematic way from sets of people who lived during a different period what do we call this Turkish?
E.g. People’s knowledge of computers should increase with age and levels off at about age 30.
Choosing between cross-sectional and longitudinal designs: cross-sectional does not control for cohort effects
E.g. Divorce leads to externalizing behaviors in children (???)
A longitudinal study says no
Disadvantage: costly and time-consuming, also attrition problem (participants may drop out before the study is completed).
Also may not be feasible for every research question. E.g. Comparing 2 years olds and 2,5 years olds on a memory test.
E.g. Kağıtçıbaşı’s study.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Influence of Early Experience
Early input from the world exerts a significant impact on development…but so does all other input throughout life.
Myths of infant determinism and childhood fragility.
Especially in the first three years of life experiences are almost always more influential than later ones in shaping us as adults.
Later experiences are not less influential.
Separating baby few hours from mom after birth has no lasting effects on emotional development.
Childeren are not resilient or incapable of withstanding stress.
Kidnapped or even sexually abused kids may emerge without severe psychological problems.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
The Nature-Nurture Debate
Both play large roles in shaping development
It’s not an “either-or” issue any longer
Hart and Risley’s (1995) study: parents who speak more to their children have kids who have larger vocabularies than parents who don’t.
Can you find out an alternative hypothesis?
Gene-environment interaction
Impact of genes on behavior depends on the environment where behavior develops
E.g. Children with low monoamine oxidase (MAO) enzyme are more prone to engage in violent behavior only when they have a history of maltreatment like physical abuse. So, it is not the only low level of MAO.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
The Nature-Nurture Debate
Nature via nurture
Children with certain genetic predispositions often seek out and create their own environments
E.g. Fearful kids seek out safe environments growing up
in safe environements result in fearfulness?
Gene expression
Activation or deactivation of genes by environmental experiences throughout development
Schizophrenia is the best example maybe
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Conception & Prenatal Development
Most dramatic changes occur during early prenatal (prior to birth) development
A zygote is formed when sperm cell fertilizes an egg
After this, three stages of development occur
Germinal stage
Embryonic stage
Fetal stage
Copyright © 2011 Pearson Education, Inc. All rights reserved. Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Prenatal Development
Zygote divides over and over again to form a blastocyst during the germinal stage
Blastocyst is a ball of identical cells that haven’t yet begun to take on any specific function in a body part
Around the middle of the second week, the cells begin to differentiate to function as different organs so,
blastocyst becomes an embryo
Embryonic stage from 2nd to 8th week; limbs, facial
features, major organs begin to take shape (risk of miscarriage)
By the 9th week Fetal stage embryo becomes a
fetus; physical maturation for the rest of the pregnancy is the job
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Prenatal Development
By the 9th week and the start of the fetal stage, the major organs are established and heart beats
The fetus continues physical maturation and “bulking up” until birth
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Brain Development
Between day 18 and the 6th month, neurons grow at an incredible rate – a process called proliferation
Up to 250,000 neurons per minute at times
Starting from 4th month
migration of cells start, neurons start to sort themselves out (e.g. Hippocampus or cerebellum)
Unlike other organs, continue to develop into even early adulthood
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Obstacles to Development
3 factors:
Exposure to hazardous environmental influences
Biological influences resulting from genetic disorders or errors in cell duplication during cell division
Premature birth
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Obstacles to Development
Teratogens are environmental factors that can exert a negative impact on prenatal development
Examples are smoking, drugs, chicken pox
Even anxiety and depression
Alcohol consumption can lead to fetal alcohol syndrome
Syndromes include: Learning disabilities, physical growth retardation, facial malformations, behavioral disorders
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Obstacles to Development
Genetic disruptions can be from disorders or random errors in cell division
Mental retardation, including Down syndrome
Prematurity, being born prior to 36 weeks, can result in numerous problems
Normal birth is given after 40 weeks of pregnancy
The less time in utero, the greater chance of serious complications
Viability point: the point in pregnancy at which infants can survive on their own is around 25 weeks
Those who born 22 weeks can also survive; but with physical and cognitive impairments
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Motor Development
Infants are born with a large set of automatic motor behaviors (reflexes)
Sucking and rooting reflexes
Motor behaviors are bodily motions that occur as result of self-initiated force that moves the bones and muscles
Sitting up – 6 months, crawling – 9 months, standing unsupported – 11 months, walking – 13 months, running – 18-24 months
Copyright © 2011 Pearson Education, Inc. All rights reserved. Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Factors Affecting Motor Development Wide range in the rate and manner in which children achieve motor
milestones
Influenced by physical maturity, as well as cultural and parenting practices
In Peru and China – tightly swaddled in blankets, limiting free movement of the limbs
African and West Indian mothers – stretching, massage, strength-building exercises with their infants
But they are always achieved in the same developmental sequence
Motor patterns are innately programmed and become activated at specific time points
Some motor achievements also depend on the physical maturation of the body
Also the body weight of the baby matters – heavier babies tend to achieve milestones more gradually
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Physical Development in Childhood
The relative size of our body parts changes dramatically during first 20 years
Infants – no neck, head almost half the size of torso, arms don’t even reach the top of the head
Growth spurts are real
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Adolescence
Transitional period between childhood and adulthood commonly associated with the teenage years
This is when our bodies reach full maturity, in part due to hormonal release
The pituitary gland stimulates physical growth and the reproductive system releases sex hormones into the bloodstream triggering growth and other physical changes
Estrogens and androgens – both types of hormones are present in both sexes in varying proportions
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Adolescence
Testesterone in boys: Increases in muscle tissue, growth of facial and body hair, broadening of the shoulders
Estrogens in girls: Breast growth, uterus and vaginal maturation, hip broadening, onset of menstruation
Androgens in girls: Physical growth and the growth of pubic hair
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Adolescence
Attainment of puberty (sexual maturation – the attainment of physical potential for reproduction) is largely due to that hormonal release
Causes changes in primary (reproductive organs and genitals) and secondary sex characteristics (sex-differentiating characteristics that are not directly related to reproduction)
Menarche (the onset of menstrution) and spermarche (the first ejaculation – around age 13)
Menarche – body’s insurance plan againist allowing girls to become pregnant before their bodies can carry an infant to term and give birth safely
Genetic and environmental factors (e.g., SES) influence timing of puberty
Copyright © 2011 Pearson Education, Inc. All rights reserved. Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Physical Development in Adults
Most of us reach our physical peaks in early 20s
Strength, coordination, speed of cognitive processing, and physical flexibility
Declines begin shortly after, including muscle, sensory processes, and fertility
Menopause signals the end of a female’s reproductive ability
Triggered by decrease in estrogen – hot flahes; hot, sweaty, and dry-mouthed, mood swings, sleep disruption, and temporary loss of sexual drive or pleasure
These effects vary across cultures – 50 percent of American women vs. 15 percent of Japanese women. Why?
Changes in agility and physical coordination with age – Variations are great
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Theories of Cognitive Development
Numerous explanations of how we acquire the ability to learn, think, communicate, and remember over time
Differ in three ways
Stagelike (sudden spurts followed by periods of stability) vs gradual changes in understanding
Domain-general vs domain-specific
Principal source of learning
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Jean Piaget
Swiss psychologist who presented first complete account of cognitive development
Stage theorist who believed skills were domain-general
Led to formation of cognitive development as a distinct discipline
Showed that childrens’ understanding of the world fundementally differs from adults’
Children are not passive observers of their worlds, but active learners who seek info and observe the results of their actions
Thought end point of cognitive development is ability to reason logically about hypotheticals
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Piaget’s Theory
Cognitive change is marked by equilibration – maintaining a balance between what we experience and what we think about it
Children use assimilation to acquire new knowledge within a stage
When one can no longer assimilate new information, accommodation forces change between stages
What shape is the Earth?
Copyright © 2011 Pearson Education, Inc. All rights reserved. Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Piaget’s Stages
Four stages, each with a specific way of looking at the world and cognitive limitations
Sensorimotor (birth – 2 years)
Focus on the here and now
Lack object permanence (the understanding that objects continue to exist even when out of view) and deferred imitation (the ability to perform an action observed earlier)
Major milestone is mental representation
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Piaget’s Stages
Preoperational stage (2 – 7 years)
Marked by an ability to construct mental representations of experience
E.g. Banana is a phone, hair brush is a microphone (displaying symbolic behavior)
Hampered by egocentrism (inability to see the world from others’ point of view) and inability to perform mental operations
Piaget’s three mountain task
Lack conservation
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Piaget’s Stages
Concrete operations (7 – 11 years)
Can perform mental operations, but only for actual physical events
Can pass conservation tasks
Formal operations (11 – adulthood)
Can understand hypothetical reasoning beyond the here and now
Logical concepts like if-then statements and either-or statements
Also logical concepts and abstract questions such as meaning of life
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Pros and Cons of Piaget
Inaccurate in a number of ways
Development is more continuous
Horizontal decalage – cases in which a child is more advanced in one cognitive domain than another
Probably underestimated children’s competence
Culturally biased methods
Many observations were based on formally educated children and his own three children
Still, highly influential and helped change how we think about cognitive development
Viewing children as different in kind rather than degree from adults
Characterizing learning as an active process
Exploring general cognitive processes that may cut across multiple domains of knowledge
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Lev Vygotsky
Theory focused on social and cultural influences on cognitive development
Parents structure environments for learning and then gradually remove it (scaffolding)
Zone of proximal development (the phase when children are receptive to learn a new skill but aren’t yet successful at it) and developmental readiness for learning
Piaget emphasized physical interaction with the world as the primary source and Vygotsky emphasized social interaction
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Contemporary Theories
General cognitive accounts
General cognitive processes and experience-based learning but not stagelike; rather gradual
Sociocultural accounts
Social context and interaction with caregivers
Modular accounts
Domain-specific learning, separate spheres of knowledge in different domains
Understanding of language may be independent of the ability to reason about space
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Cognitive Landmarks
Aside from accomplishments in perception, memory, and language, there are many others
Naïve physics and how physical objects behave
E.g. İnfants know that an object that is unsupported should fall
Categorizing objects by kind
Even infants showing pictures study
Categorizing is crucial
Concept of self and others and theory of mind (ability to reason about what other people believe)
Even by three months of age self as distinct from others
12 months recognize own image on mirror
2 years call their names on a photo
False belief task to test the theory of mind most children do not pass until they are 4 or 5
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Cognitive Landmarks
Aside from accomplishments in perception, memory, and language, there are many others
Counting and math
Numbers are about amount
Number words refer to specific quantities
Numbers are ordered from smallest to largest in quantity
Two elephants is the same number as two grains of rice – so, size of entities isn’t relevant to quantities this insight is extremely difficult for children
Cross-cultural differences in how parents and teachers introduce counting and linguistic differences about numbers (e.g., «twelve» vs «one ten two»)
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Cognitive Changes in Adolescence
Frontal lobes don’t fully mature until late adolescence or early adulthood
Also limbic structures involved in social reward systems become more active vulnerable to deviant peer group
influences
Personal fable and feeling unique and special
Teens may just not care about risks
Changing attitudes toward knowledge
Frustrated by the answer «it depends» during college years
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Cognitive Function in Late Adulthood
Many aspects of cognition decline
Ability to recall information (decreasing volume in the cortex and the hippocampus)
Overall speed of processing (that’s why you beat your father on video games )
But many stay stable or increase
Cued recall and recognition – remain intact
Remembering pertinent information – little decline
Vocabulary and knowledge tasks – better than youngers!
Older is wiser
Copyright © 2011 Pearson Education, Inc. All rights reserved.
THE DEVELOPMENT OF PERSONALITY: SOCIAL AND MORAL DEVELOPMENT Early Social Development
Infants develop interest in other people very quickly after birth
Prefer looking at faces over other objects, as early as 4 days prefer to look at mother’s face over another woman’s face
Stranger (eight months) anxiety starts at 8-9 months, peaks at 12-15 months, then declines
Adaptive mechanism to keep infants away from danger; makes evolutionary sense since it is universal
Differences in children’s social and emotional styles reflect differences in temperament
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Temperament
Early appearing and largely genetic
Three major styles (Thomas & Chess, 1977)
Easy (40%)
Difficult (10%)
Slow-to-warm up (15%)
Approximately 10% of children may be behaviorally inhibited – like «scaredy cats» (Kagan et al., 2007)
Inhibition not at all bad – kids with very low levels of inhibition may be at risk for impulsive behaviors as adolescents
There are cultural differences in temparement which are observed among as early as 4-day-old infants
Environmental factors may alter, although it is mostly genetic
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Attachment
Emotional connection we share with those to whom we feel closest
Lorenz’s study with goslings
Imprinting (even with moving objects) and possible sensitive periods for healthy interpersonal relationships
Rutter’s studies of Romanian orphans: those adopted after 6 months of age more serious emotional and
psychological problems
There is another possible explanation (they were more difficult to begin with, so they were placed later) but replicated in studies with various methods
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Contact Comfort
Behaviorists assumed children bonded with those that provided them nourishment
Harry Harlow’s work with rhesus monkeys showed otherwise (wire mother vs terry cloth mother)
http://www.youtube.com/watch?v=KlfOecrr6kI
Reassuring physical contact played huge role in developing attachment
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Attachment Styles
Refers to how infants react when separated from primary caregiver
Strange Situation task with 1-year old kids (Ainsworth et al., 1978)
Four categories of behavior
Secure attachment (60%): Mom is the secure base
Insecure-avoidant attachment (15%-20%): Indifferent mom’s departure and coming back
Insecure-anxious attachment (15%-20%): Panics, but mixed emotional responses when mom returns
Disorganized attachment (5%-10%): Inconsistant and confused set of responses when mom comes back
Copyright © 2011 Pearson Education, Inc. All rights reserved. Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved. Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved. Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Attachment Styles
Show large cultural differences
Japan: More insecure-anxious; USA: Insecure-avoidant
Subject to the mono-operations bias; the mistake of relying on only a single measure to draw conclusions; Strange situation is only one method to measure or one indicator of attachment style
Lack of reliability on the Strange Situation
Changing styles over brief times
Different styles for mom vs dad (40% of infants)
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Parenting Styles (Baumrind, 1971, 1991)
Permissive – tend to be lenient, little discipline, very affectionate (FALL BETWEEN)
Authoritarian – Very strict, punishing, little affection (FALL BETWEEN)
Authoritative – Supportive but set clear and firm limits (BEST)
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Parenting Styles
Uninvolved – neglectful and ignoring (WORST)
Cultural differences
May not matter as much as once thought, as long as an average expectable environment is provided
Matter most if they are toxic or child is genetically predisposed towards impulsivity or violent behavior
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Other Parenting Issues
Relative influence of peers vs parents on social development – Harris’s (1995) group socialization theory of development
Fathers differ from mothers in several ways
Less attentive and affectionate towards babies
Spend less time with babies
More time in physical play
Preferred as playmates by children
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Other Parenting Issues
Impact of single-parenthood on children is unclear
A lot of confounding variables such as SES, high stress, etc.
Impact of same-sex parents on development is much clearer
No difference from opposite-sex couples in social adjustment, academics, or sexual orientation
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Other Parenting Issues
Most children come out of divorce without long-term emotional damage
Effects depend on severity of conflict prior to the divorce
The higher the conflict the better the outcome
ANOTHER ISSUE: Impulse control, Mischel’s delay of gratification experiment
http://www.youtube.com/watch?v=Yo4WF3cSd9Q
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Development of Gender Identity
Sex refers to biological status, gender to psychological characteristics
Gender identity vs gender role
As a woman may have a female identity but act very different from traditional gender role, vice versa
Biological influence on gender differences
Which toys are played with
Sex segregation during play (3 years old)
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Development of Gender Identity
Social influences also play a role in gender development
Encouragement of types of behavior
Expectations of behavior (jack-in-the-box experiment; anger vs fear perceptions for same startled reaction )
Gender-role socialization tends to be stricter for boys than girls
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Social and Emotional Development in Adolescence
One main challenges during adolescence is development of an identity – who we are, our goals and priorities
Erikson developed a comprehensive model to explain identity development
Slim research basis for support, though
ANOTHER ISSUE: Emerging Adulthood Period between 18
and 25 (role experimentation time)
Copyright © 2011 Pearson Education, Inc. All rights reserved. Copyright © 2011 Pearson Education, Inc. All rights reserved.
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Kohlberg’s Moral Development
Used several moral problems to see what principles people used to solve them
Three major stages
Preconventional – focus on punishment and reward
Conventional – focus on societal values
Postconventional – focus on internal moral principles
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Criticisms
Cultural bias - individualist vs. collectivist cultures
Sex bias - ‘justice’ vs. ‘caring’ orientations
Low correlation with moral behavior
Confounded with verbal intelligence
Assumes moral reasoning precedes emotional reaction to moral issues
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Life Transitions in Adulthood
Careers and job satisfaction
Average Americans change jobs 10.5 times between ages of 18 and 40
U shaped curve on job satisfaction over the life span
Love and commitment
Parenthood
More realistic expectations are required to adapt more easily
Marital satisfaction decreases and rebounds once children reach school age
Copyright © 2011 Pearson Education, Inc. All rights reserved.
Social Transitions in Later Years
Midlife crisis (a myth) and empty nest syndrome (overstated, may be particular to Caucasian women who don’t work outside the house)
Sandvich generation – caring both their own kids and their old parents
Chronological age is not a good predictor of measuring impact of changes in later life
Instead, consider others that may be more indicative
Biological, psychological, functional, and social age