Psychology Chapter 8: Development Across the Life Span

Human development

the scientific study of the changes that occur in people as they age from conception until death.

Longitudinal design

research design in which one participant or group of participants is studied over a long period of time to determine age-related changes.

Cross-sectional design

research design in which several different participant age-groups are studied at one particular point in time to determine age-related differences.

Cohort effect

the impact on development occurring when a group of people share a common time period or common life experience.

• ex: the cognitive and social changes of children born into an age of smartphones

Cross-sequential design

research design in which participants are first studied by means of a cross-sectional design but are also followed and assessed longitudinally to determine both age-related changes and differences.

Nature

the influence of our inherited characteristics on our personality, physical growth, intellectual growth, and social interactions.

Nurture

the influence of the environment on personality, physical growth, intellectual growth, and social interactions.

Genetic

the science of inherited traits.

DNA (deoxyribonucleic acid)

special molecule that contains the genetic material of the organism.

Gene

section of DNA having the same arrangement of chemical elements.

• specific physical and behavioral traits are dependent upon pairing of genes; more active genes are dominant, others are recessive

• most traits are from polygenic inheritance (coming from many genes)

Chromosome

tightly wound strand of genetic material or DNA.

• aside from egg and sperm, humans have 46 chromosomes in each cell of the body

• we get 23 from the mother’s egg and 23 from the father’s sperm

Autosomes

most characteristics are determines by these 22 chromosome pairs

Sex chromosomes

the last pair that determines the sex of the person

Genetic disorders

• those carried by dominant genes are expressed when a child gets one or two dominant genes (ex: Huntington’s syndrome)

• those carried by recessive genes are expressed when a child gets two recessive genes (ex: cystic fibrosis)

• issue may also occur if chromosomes have an extra (ex: Down syndrome) or a missing pair (ex: Turner syndrome)

Prenatal development

has three stages spanning the approximately 9 months from conception to the birth of the baby

Fertilization, the zygote, and twinning

• egg and sperm unite through process of fertilization, resulting in a single cell (zygote) that has 46 chromosomes

• through mitosis, zygote begins to divide, into two cells, then four, etc. until baby is form

• alterations in mitosis can result in twins or multiples

Monozygotic (identical) twins

identical twins formed when one zygote splits into two separate masses of cells, each of which develops into a separate embryo.

Dizygotic (fraternal) twins

often called fraternal twins, occurring when two individual eggs get fertilized by separate sperm, resulting in two zygotes in the uterus at the same time.

Germinal period

2-week period following fertilization

• zygote continues dividing and moving toward the uterus

• the placenta and umbilical cord also develop during this time

• cell differentiation occurs

Cell differentiation

the process that results in specialized cells for all of the various parts of the body

Embryonic period

2 weeks after conception to 8 weeks

• once attached to the uterus, developing organism is called an embryo

• cell specialization continues to occur, resulting in the preliminary versions of various organs

• critical periods are most pronounced in this stage; embryo is vulnerable to hazards such as diseases and substances ingested by the mother as it receives nourishment through the placenta

Critical periods

times during which certain environmental influences can have an impact on the development of the infant.

Teratogen

any factor that can cause a birth defect.

Fetal alcohol spectrum disorders (FASDs)

a group of conditions caused by a mother consuming alcohol during pregnancy, in which a combination of physical, mental, and behavioral problems may be present.

Fetal period

From about 8 weeks to birth

• developing organism now called a fetus; time of tremendous growth and development

• organs continue to develop and become fully functional

• full-term birth occurs around end of 38th week

• miscarriages (spontaneous abortions) are most likely to occur in the first three months

Age of viability

the point at which it is possible for an infant to survive outside the womb

• between 22 (30% chance of survival) and <26 weeks (89% chance of survival)

Physical development of infancy and childhood

immediately after birth, body systems start to function (respiratory, circulatory, temperature regulation, digestive)

• babies are born with (innate) reflex behaviors

Infant reflexes

• grasping

• startle/Moro

• rooting

• stepping

• sucking

Motor development of infancy and childhood

Birth to 2 years = period of rapid development

As with physical and sensory development, normal motor development is related to many factors, such as nutrition, care, and health

• 2-4 months: raising head and chest

• 2-5 months: rolling over

• 4-6 months: sitting up with support

• 6-7 months: sitting up without support

• 7-8 months: crawling

• 8-18 months: walking

Sensory development of infancy and childhood

• touch, taste, and smell are well developed

• hearing is functional but not fully developed

• vision is least developed (rods are functional, cones take about 6 months to fully develop)

Visual cliff

a research tool used to study depth perception in infants, demonstrating early perceptual abilities

Cognitive development

the development of thinking, problem-solving, and memory

Piaget’s Four Stages of Cognitive Development

• suggests children form mental concepts or schemas as they experience new situations and events

• proposes four distinct stages of cognitive development that span infancy to adolescence

Assimilation (Piaget)

understanding new things in terms of schemas they already possess

Accommodation (Piaget)

understanding through altering or adjusting old schemas to fit new information

Sensorimotor stage (Piaget)

birth to 2 years old

first stage of cognitive development, in which the infant uses its senses and motor abilities to interact with objects in the environment

• have fully developed object permanence by the end of the stage

Object permanence (Piaget)

the knowledge that an object exists even when it is not in sight.

Preoperational stage (Piaget)

2 to 7 years old

second stage of cognitive development, in which the preschool child learns to use language and symbols as a means of exploring the world

• animism

• egocentrism

• centration

• lacks conservation

• irreversibility

Animism (Piaget)

belief of a preoperational child that everything is alive and has feelings just like their own

Egocentrism (Piaget)

the inability to see the world through anyone else’s eyes.

Centration (Piaget)

the tendency of a young child to focus only on one feature of an object while ignoring other relevant features.

Conservation (Piaget)

the ability to understand that simply changing the appearance of an object does not change the object’s nature.

Irreversibility (Piaget)

the inability of the young child to mentally reverse an action.

Concrete operations stage (Piaget)

ages 7-12

third stage of cognitive development, in which the school-age child becomes capable of logical thought processes but is not yet capable of abstract thinking.

Formal operations stage (Piaget)

last stage of cognitive development, in which the adolescent becomes capable of abstract thinking (hypotheticals, deductive reasoning, mathematics, etc.).

• not everyone reaches this tage

Vygotsky’s theory

• stresses the importance of social interactions with others, typically more highly skilled children and adults

• children’s cognitive development occurs when someone helps them by asking leading questions and providing examples of concepts (scaffolding)

• each child has a zone of proximal development

Scaffolding (Vygotsky)

process in which a more-skilled learner gives help to a less-skilled learner, reducing the amount of help as the less-skilled learner becomes more capable.

Zone of proximal development (ZPD) (Vygotsky)

the difference between what a child can do alone and what that child can do with the help of a teacher.

Autism spectrum disorder (ASD)

neurodevelopmental disorder that involves issues in thinking, feeling, language, and social interactions

• causes are still being investigated but extensive research has found no link to any childhood immunizations; genetic mutations and changes in brain areas may be involved

Psychosocial development

involves development of personality, relationships, and a sense of gender identity

• process begins in infancy and continues into adulthood

Temperament

the behavioral characteristics that are fairly well established at birth, such as “easy,” “difficult,” and “slow to warm up”; the enduring characteristics with which each person is born

• can also affect, and is affected by, parenting and the environment

“Easy” temperament

• regular in their schedules of waking, sleeping, and eating

• are adaptable to change

• happy babies that, when distressed, are easily soothed

“Difficult” temperament

• tend to be irregular in their schedules

• are very unhappy about change of any kind

• are loud, active, and tend to be crabby rather than happy

“Slow to warm up” temperament

• are less grumpy, quieter, and more regular than difficult children but who are slow to adapt to change

• if change is introduced gradually, these babies will “warm up” to new people and new situations

Attachment

the emotional bond between an infant and a primary caregiver.

• appear to be similar, but not identical, across different cultures

• may be affected by the “goodness of fit” between the child’s temperament and that of their parent(s)

“Strange situation” experiment

Conducted by Mary Ainsworth exposing an infant to a series of leave-takings and returns of the mother and a stranger

Secure attachment

Secure babies:

• explored happily

• touched base with the mother

• were calm around strangers

• got upset when the mother left but were easily soothed upon her return

Avoidant attachment

Avoidant (unattached) babies:

• did not touch base if they explored

• were distinterested in the stranger and the mother’s absence/return

Ambivalent attachment

Ambivalent (insecurely attached) babies:

• clingy and unwilling to explore

• had high levels of separation anxiety and stranger wariness

• showed conflicting/mixed feelings about mother’s return

Disorganized-disoriented attachment

Disorganized-disoriented (insecurely attached and sometimes abused or neglected) babies:

• seemed fearful

• had a dazed or depressed look

• were unsure how to feel about their mother’s return

Harlow’s classic research with infant rhesus monkeys

demonstrated the importance of contact comfort in the attachment process, contradicting the earlier view that attachment was merely a function of associating the mother with the delivery of food

Self-concept

the image of oneself that develops from interactions with important significant people in one’s life.

Erikson’s Stages of Psychosocial Development

suggests development occurs in a series of eight stages and at each stage, an emotional crisis must be successfully met for normal development to occur

Trust vs. mistrust (first stage)

infants (birth to 1-year-old) learn a basic sense of trust dependent upon how their needs are met

• if babies’ needs for food, comfort, and affection are met, they develop a sense of trust in people and expect those needs to be met in future

• if babies’ needs for food, comfort, and affection are not met, they develop a sense of mistrust and do not expect their needs to be met in future

Autonomy vs. shame and doubt (second stage)

toddlers (1 to 3 years old) begin to understand that they can control their own actions

• toddlers who are successful in controlling their own actions develop independence

• toddlers whose attempts at being independent are blocked develop a sense of self-doubt and shame for failing

Initiative vs. guilt (third stage)

preschool children (3 to 5 years old) learn to take responsibility for their own behavior as they develop self-control

• if preschoolers succeed in controlling their reactions and behavior, they feel capable and develop a sense of initiative

• if preschoolers fail in controlling their reactions and behavior, they feel irresponsible and anxious and develop a sense of guilt

Industry vs. inferiority (fourth stage)

the elementary school-aged child (5 to 12 years old) must learn new skills in both the academic world and the social world; they compare themselves to others to measure their success or failure

• when children feel they have succeeded at learning these skills, they develop a sense of industry, making them feel competent and improving their self-esteem

• when children fail or feel that they have failed in learning these skills, they feel inferior when compared to others

Identity vs. role confusion (fifth stage)

adolescents (13 to early 20s) must decide who they are, what they believe, and what they want to be as an adult

• adolescents who are able to define their values, goals, and beliefs will develop a stable sense of identity

• adolescents who are unable to define themselves remain confused and may isolate themselves from others or try to be like everyone else instead of themselves

Intimacy vs. isolation (sixth stage)

young adults (20s and 30s) face the task of finding a person with whom they can share their identity in an ongoing, close, personal relationship

• young adults who successfully find someone and share their identities will have a fulfilling relationship founded on psychological intimacy

• young adults who are unable to find someone (often because they do not yet have a stable identity to share) will isolate themselves and may experience loneliness, even when involved in shallow relationships with others

Intimacy

an emotional and psychological closeness that is based on the ability to trust, share, and care, while still maintaining a sense of self.

Generativity vs. stagnation (seventh stage)

for middle-aged adults (40s and 50s), he focus of this task is to find a way to be a creative, productive person who is nurturing the next generation

• adults who are able to focus on the next generation will be productive and creative, leaving a legacy for the future

• adults who are unable to focus outside themselves will remain stagnated and self-centered, and feel that they have not made a difference

Generativity

providing guidance to one’s children or the next generation, or contributing to the well-being of the next generation through career or volunteer work.

Ego integrity vs. despair (eighth stage)

for older adults (60s and beyond), the task in this stage involves coming to terms with the end of life, reaching a sense of wholeness and acceptance of life as it has been

• older adults who are able to come to terms with their lives and the things they have done and left undone and are able to “let go” of regrets will have a sense of completion and will see death as simply the last stage of a full life

• older adults who have not been able to achieve identity or intimacy or generativity, who cannot let go of their regrets, will feel a sense of having left things until too late and see death as coming too soon

Ego integrity

sense of wholeness that comes from having lived a full life possessing the ability to let go of regrets; the final completion of the ego.

Adolescence

the period of life from about age 13 to the early 20s, during which a young person is no longer physically a child but is not yet an independent, self-supporting adult.

Puberty

the physical changes that occur in the body as sexual development reaches its peak.

• increase in height and changes in both primary and secondary sex characteristics

• occurs as the result of glandular and hormonal activities

• tends to occur about 2 years after beginning of growth spurt

Brain development of adolescents

continues into the 20s

• portions responsible for impulse control and decision-making (i.e. prefrontal cortex) not complete until about age 25

• this leads to risk-taking and increased vulnerability to various dangers (ex: STIs)

Cognitive development of adolescents

• continued maturation of the frontal lobes allows cognitive advances (such as the abstract thought needed for Piaget’s formal operations stage)

• despite advances, they still have egocentric thought that emerges in a variety of ways, as discovered by David Elkind

Personal fable (adolescent egocentrism)

type of thought common to adolescents in which young people believe themselves to be unique and protected from harm.

Imaginary audience (adolescent egocentrism)

type of thought common to adolescents in which young people believe that other people are just as concerned about the adolescent’s thoughts and characteristics as they themselves are.

• can become the spotlight effect in adulthood

Moral development

understanding of what is “right” and “wrong”

Kohlberg’s Stages of Moral Development

suggested three levels of moral development

• some researchers (e.g. Carol Gilligan) suggest that Kohlberg’s ideas applied more to males, although using objective measures of empathy appears to negate sex differences

• others suggest Kohlberg’s assessment was based on hypothetical, rather than real-life, dilemmas

Preconventional morality (Kohlberg)

morality of an action is based on the consequences; actions that get rewarded are right and those that earn punishment are wrong.

• associated with very young children

Conventional morality (Kohlberg)

an action is morally right if it conforms to the rules of the society and wrong if it does not

• associated with older children, adolescents, and most adults

Postconventional morality (Kohlberg)

morality is now determined by the experiences and judgment of the person, even if that judgment disagrees with society’s rules

• found in about one-fifth of the adult population

Psychosocial development of adolescents

largely marked by the search for a consistent sense of self or personal identity

• Erikson: the psychosocial crisis that must be resolved is identity vs. role confusion

• parent/teen conflict is to be expected

Adulthood

the period of life from the early 20s until old age and death

Physical development of young adulthood

few changes; the 20s are typically associated with peak physical and cognitive health

Physical development of middle age

• hearing and vision begin to decline; weight increase in typical while height starts to decrease

• females experience menopause; males experience less dramatic change called andropause

• health problems related to genetics and lifestyle when younger start to appear

Menopause

the cessation of ovulation and menstrual cycles and the end of a female’s reproductive capability.

Andropause

gradual changes in the sexual hormones and reproductive system of middle-aged males.

Physical development in late adulthood

• further decline in hearing; by the 60s or 70s, hearing loss is now noticeable and may require the use of hearing aids

• physical strength declines

• people with osteoporosis may lose up to 8 inches in height

Cognitive development in adulthood

• cognitive skill often highest in 20s; processing and reaction time slow in middle age but are often compensated by greater life and situational knowledge

• memory issues begin in middle age, likely due to stress and information overload

• mental abilities aided by active cognitive engagement (working on challenging puzzles or crosswords, playing cards or chess, etc.) and physical activity

Psychosocial development in adulthood

• from late adolescence through the 20s in developed countries, some may experience period of emerging adulthood

• typical life concerns involve career, relationships, family and approaching old age

• Erikson’s psychosocial concerns of adulthood: intimacy versus isolation; generativity versus stagnation (especially as it relates to parenting); integrity versus despair

Emerging adulthood

a time from late adolescence through the 20s referring to those who are childless, do not live in their own home, and are not earning enough money to be independent, mainly found in developed countries.

Authoritarian parenting

style of parenting in which parent is rigid and overly strict, showing little warmth to the child.

Permissive parenting

style of parenting in which parent makes few, if any, demands on a child’s behavior.

• can be permissive neglectful or permissive indulgent

Permissive neglectful (parenting)

permissive parenting in which parent is uninvolved with child or child’s behavior.

Permissive indulgent (parenting)

permissive parenting in which parent is so involved that children are allowed to behave without set limits.

Authoritative parenting

style of parenting in which parent combines warmth and affection with firm limits on a child’s behavior.