Unit 3: Development and Learning

Developmental psychology

The study of how and why people change over time, including physical, cognitive, and social-emotional development.

Chronological development

An approach that emphasizes the sequence and timing of age-related changes (developmental milestones).

Thematic development

An approach that focuses on recurring debates across the lifespan (e.g., nature vs. nurture; continuity vs. stages; stability vs. change).

Nature

Genetic and biological influences on development (e.g., inherited traits, brain maturation, predispositions).

Nurture

Environmental influences on development (e.g., parenting, education, culture, nutrition, stress, peers).

Gene–environment interaction

The idea that genes influence responses to environments and environments can influence how genes are expressed; development reflects their interplay.

Continuous development

Gradual, quantitative change over time (e.g., steadily increasing vocabulary).

Discontinuous (stage-like) development

Qualitative shifts in thinking or behavior that occur in distinct stages (e.g., Piaget’s stage theory).

Stability

The tendency for certain traits to remain relatively consistent across time (e.g., aspects of temperament/personality).

Critical period

A limited time window when specific experiences have an especially powerful effect on development.

Sensitive period

A broader window when learning is easier and the brain is especially receptive, though outcomes are not as all-or-none as in critical periods.

Plasticity

The brain’s ability to change in response to experience, often greatest early in life and during sensitive periods.

Cross-sectional study

A design that compares different age groups at one point in time; efficient but can be confounded by cohort effects.

Cohort effect

Differences due to being born/raised in different generations that can be mistaken for age-related development in cross-sectional research.

Longitudinal study

A design that follows the same individuals over time to track within-person change; costly and vulnerable to attrition.

Attrition

Participant dropout over time in a longitudinal study, potentially biasing results.

Maturation

Biologically driven growth and change (e.g., brain development, physical growth).

Germinal (zygote) stage

Prenatal stage from conception to about 2 weeks, marked by rapid cell division and implantation.

Implantation

The process by which the fertilized egg attaches to the uterine wall during the germinal stage.

Embryonic stage

Prenatal stage roughly weeks 3–8 when major organs and body structures begin forming; a particularly sensitive period.

Fetal stage

Prenatal stage from about week 9 to birth, characterized by rapid growth and maturation of organs and systems.

Teratogen

Any harmful agent that can disrupt prenatal development (e.g., alcohol, drugs, certain infections, toxins).

Fetal Alcohol Spectrum Disorders (FASD)

A range of physical, cognitive, and behavioral outcomes linked to prenatal alcohol exposure.

Down syndrome

A genetic disorder caused by an extra copy of chromosome 21.

Sickle cell anemia

A genetic disorder caused by a mutation in the hemoglobin gene, affecting red blood cells and oxygen transport.

Rooting reflex

An infant reflex in which the baby turns toward a cheek touch and begins to suck, helping locate nourishment.

Moro (startle) reflex

An infant reflex involving a startle response (e.g., arm extension) to a sudden loss of support or loud noise.

Synaptic pruning

A brain process that strengthens frequently used neural connections and eliminates many unused ones, increasing efficiency.

Gross motor skills

Motor abilities using large muscles for movement (e.g., crawling, walking, running).

Fine motor skills

Motor abilities involving precise hand and finger movements (e.g., grasping, drawing, manipulating objects).

Visual cliff

A method (Gibson & Walk) using a glass-covered “drop-off” illusion to test infant depth perception, typically evident by 6–8 months.

Imprinting

A rapid, instinctive attachment formed during a critical period in some animals to the first moving object encountered (shown by Lorenz).

Puberty

The transition to reproductive maturity triggered by hormonal changes, including activation of the hypothalamic-pituitary-gonadal (HPG) axis.

Primary sex characteristics

Physical features directly involved in reproduction (e.g., testes/penis and sperm production; ovaries/uterus and menstruation).

Secondary sex characteristics

Non-reproductive physical changes at puberty (e.g., breast development, facial hair, voice changes).

Menarche

The onset of menstruation in females, marking reproductive maturation.

Spermarche

The first ejaculation/sperm production in males, marking reproductive maturation.

Menopause

Cessation of menstruation, typically around age 50, reflecting the end of female reproductive capacity.

Fluid intelligence

The ability to reason quickly and solve novel problems; often shows more age-related decline than crystallized intelligence.

Crystallized intelligence

Accumulated knowledge, vocabulary, and expertise; often maintained longer across adulthood than fluid intelligence.

Schema

A mental framework used to organize and interpret information (Piaget).

Assimilation

Interpreting new experiences using existing schemas (e.g., calling a wolf a “dog”).

Accommodation

Modifying schemas to incorporate new information (e.g., creating a separate category for “wolf”).

Object permanence

The understanding that objects continue to exist even when out of sight, developing in Piaget’s sensorimotor stage.

Preoperational stage

Piaget’s stage (about ages 2–7) marked by symbolic thought but limited logical reasoning (e.g., egocentrism, centration).

Conservation

The understanding that quantity remains the same despite changes in shape or appearance; improves in the concrete operational stage.

Zone of proximal development (ZPD)

Vygotsky’s concept: tasks a learner cannot do alone yet but can do with guidance.

Scaffolding

Temporary support (hints, prompts, modeling) that is gradually removed as a learner becomes more competent (Vygotsky).

Metacognition

Awareness and understanding of one’s own thinking and learning strategies, supporting self-monitoring and effective studying.

Attachment

An emotional bond in which a caregiver provides a secure base for exploration and comfort during distress.