Developmental Psychology: Life Span Development

Study Guide - Smart Notes

Tailored notes based on your materials, expanded with key definitions, examples, and context.

Developmental Psychology

Introduction to Developmental Psychology

Developmental psychology is the scientific study of how and why human beings change over the course of their life. It focuses on physical, cognitive, social, and emotional development from conception to old age.

Origins: Examines the emergence and development of mind and body throughout the life span.
Central Questions: Sources of variability, plasticity, continuity vs. discontinuity, and reasons for individual differences.

Illustration of life span development from infancy to old age

Nature and Nurture in Development

The nature-nurture issue explores the degree to which environment and heredity influence behavior and development.

Nature: Genetic inheritance and biological factors.
Nurture: Environmental influences, including upbringing and experiences.
Behavioral Geneticists: Study the effects of heredity on behavior.

Table of characteristics influenced by genetic factors

Genetic Studies

Identical Twins: Genetically identical, useful for studying genetic influence.
Fraternal Twins: Share 50% of genes, same womb.
Siblings: Share 50% of genes, different wombs.
Adopted Children: Little genetic overlap, useful for studying environmental influence.

Images of identical and fraternal twins

Research Techniques in Developmental Psychology

Cross-sectional Research: Compares people of different ages at the same point in time.
Longitudinal Research: Investigates behavior as participants age, tracking changes over time.
Sequential Research: Combines cross-sectional and longitudinal approaches.

Prenatal Development

Genetics and Conception

Chromosomes: Structures containing hereditary information.
Genes: Units of heredity composed of DNA.
Zygote: Single cell formed by union of egg and sperm.

Sperm approaching egg Fetus in womb

Stages of Prenatal Development

Germinal Period: First two weeks after conception.
Embryonic Period: Weeks 2 through 8; major organs develop.
Fetal Period: From 8 weeks until birth; growth and maturation.
Age of Viability: Point at which fetus can survive if born prematurely (around 22 weeks).

Prenatal Environmental Influences

Teratogens: Environmental agents (drugs, chemicals, viruses) that can cause birth defects.
Mother’s Nutrition and Illness: Can impact fetal development.
Mother’s Emotional State and Drug Use: Includes alcohol and nicotine.

Infancy and Childhood

Physical Development

Neonate: A newborn child.
Growth: Birth weight typically triples in the first year; height increases by about half.
Brain Development: Synaptogenesis, myelination, and synaptic pruning.

Physical development from birth to childhood Development of senses in infants

Motor Development

Reflexes: Unlearned, involuntary responses (rooting, sucking, gag, startle, Babinski).
Voluntary Movements: Coordination of behavior in smooth, integrated sequences.

Milestones of voluntary movements in infants

Cognitive Development

Piaget’s Sensorimotor Stage: Birth to 2 years; knowledge through sensory and motor activities.
Object Permanence: Understanding that objects exist independent of actions.

Social Development: Attachment

Attachment: Positive emotional bond between child and adult.
Imprinting: Critical period for attachment to first moving object (studied by Konrad Lorenz).
Harlow’s Study: Wire monkey vs. cloth monkey experiment.

Harlow's wire and cloth monkey experiment

Attachment Styles

Secure: Child uses caregiver as a safe base.
Insecure: Includes avoidant, ambivalent, and disorganized styles.

Illustration of attachment styles: anxious, avoidant, secure

Peer Relationships and Social Development

Peer Relationships: Games with rules, perspective taking, emotional self-control.
Vygotsky’s Theory: Cognitive development through social interaction; Zone of Proximal Development (ZPD).

Parenting Styles

Parenting styles influence social and emotional development.

Parenting Style	Parent Behavior	Type of Behavior Produced in Child
Authoritarian	Rigid, punitive, strict standards	Unsociable, unfriendly, withdrawn
Permissive	Lax, inconsistent, undemanding	Immature, moody, dependent, low self-control
Authoritative	Firm, sets limits and goals, uses reasoning	Good social skills, likable, self-reliant, independent
Uninvolved	Detached emotionally, provides only basic needs	Indifferent, rejecting behavior

Table of parenting styles and their effects

Adolescence

Physical Development

Puberty: Maturation of sexual organs; girls (11-12 years), boys (13-14 years).
Menstruation and Spermarche: Onset of reproductive capability.

Graph of puberty milestones for males and females

Brain Development

Frontal Lobes: Memory, decision making, reasoning, impulse control.
Limbic System: Expression and interpretation of emotions.
Plasticity: Increased vulnerability to addiction and risky behaviors.

Diagram of adolescent brain regions

Moral and Cognitive Development

Kohlberg’s Theory: Three levels of moral reasoning: preconventional, conventional, postconventional.
Criticisms: Focuses on judgments, not behavior; Western bias.

Identity Formation

Erikson’s Theory: Identity vs. role confusion; exploration and commitment.

Adulthood and Aging

Physical and Social Changes

Emerging Adulthood: Late teens to mid-twenties.
Peak Health: Early adulthood; slight decline after 25.
Menopause: End of fertility in women.
Midlife Transition: Period of questioning and possible crisis.

Couple in adulthood Elderly couple

Cognitive Changes in Late Adulthood

Fluid Intelligence: Information-processing skills; declines in late adulthood.
Crystallized Intelligence: Accumulated knowledge; remains steady.
Senility: Progressive deterioration of mental abilities.
Alzheimer’s Disease: Irreversible decline in cognitive abilities.

Illustration of aging and late adulthood