Developmental Theories and Theorists: Foundations of Lifespan Psychology

Developmental Theories and Theorists

Overview

This section introduces the major perspectives and foundational issues in developmental psychology, focusing on how individuals change and grow across the lifespan. Key debates, theorists, and theoretical models are outlined to provide a comprehensive understanding of human development.

Lifespan Perspective on Development

Periods of Development

• Prenatal: Conception to birth

• Infancy and Toddlerhood: Birth to 2 years

• Early Childhood: 2 to 6 years

• Middle Childhood: 6 to 11 years

• Adolescence: 12 to 18 years

• Emerging Adulthood: 18 to mid-20s (sometimes included as a distinct stage)

These periods are social constructions and may vary across cultures.

Conceptions of Age

• Chronological Age: Number of years since birth

• Biological Age: Age in terms of biological health

• Psychological Age: Adaptive capacities compared to others of the same chronological age

• Social Age: Social roles and expectations relative to chronological age

Major Issues in Developmental Psychology

Nature versus Nurture

• Nature Theorists: Emphasize biological, genetic, and innate influences on development (e.g., heredity, maturation)

• Nurture Theorists: Emphasize the role of environment, learning, and experience in shaping development and behavior

Key Quote: John B. Watson (1924) argued that with the right environment, any child could be shaped into any type of specialist, regardless of their background.

Continuity versus Discontinuity

• Continuity: Development is smooth and gradual; changes are quantitative (more or less of the same ability)

• Discontinuity: Development occurs in distinct stages; changes are qualitative (new ways of thinking or behaving)

Modern View: Most developmental psychologists adopt a both/and position, recognizing that some aspects of development are continuous while others are stage-like, depending on the domain studied.

Active versus Passive Learning

• Active: Children are agents in their own learning, exploring and constructing knowledge

• Passive: Children are shaped by external forces and experiences

Stability versus Change

• Stability: Traits and behaviors remain consistent over time

• Change: Traits and behaviors can be modified by experience and environment

Historical and Contemporary Theories

Historical Theorists

• John Locke: Children are born as a blank slate (tabula rasa), shaped by experience

• Jean-Jacques Rousseau: Development follows a natural, stage-like roadmap

• Arnold Gesell: Development unfolds in fixed patterns based on biological motor maturity

Major Theoretical Approaches

• Psychoanalytic Theories

• Cognitive-Developmental Theory

• Behaviorism and Social Learning

• Information-Processing Approaches

• Ethological and Evolutionary Theories

• Life-Span Developmental Theory

Psychoanalytic Theory

Sigmund Freud (1856–1939)

• Emphasized the role of early childhood experiences in shaping personality and development

• Introduced the concept of the unconscious mind

Behaviorism

Key Concepts

• Focuses on how environmental stimuli and reinforcement shape observable behavior

• Emphasizes what can be directly measured and tested scientifically

Classical Conditioning (Ivan Pavlov, 1880–1937)

• Classical conditioning: Learning by associating two stimuli

• Unconditioned stimulus (UCS): Naturally elicits a response

• Unconditioned response (UCR): Automatic response to UCS

• Conditioned stimulus (CS): Previously neutral, elicits response after pairing

• Conditioned response (CR): Learned response to CS

Example: Dog salivates (CR) to bell (CS) after bell is repeatedly paired with meat (UCS).

Learning Theorists

• John B. Watson: Founder of behaviorism; emphasized observable behavior and environmental conditioning

• Little Albert Experiment: Demonstrated that fear can be classically conditioned in humans

Operant Conditioning (B. F. Skinner, 1904–1990)

• Humans select behaviors in response to consequences

• Reinforcers: Increase likelihood of behavior

• Punishers: Decrease likelihood of behavior

Types of Contingencies

• Positive Reinforcement: Add something to increase behavior

• Negative Reinforcement: Remove something to increase behavior

• Positive Punishment: Add something to decrease behavior

• Negative Punishment: Remove something to decrease behavior

Types of Reinforcers

Primary Reinforcers	Secondary Reinforcers
Unconditioned (e.g., food)	Conditioned (e.g., money)

Immediate vs. Delayed Reinforcement

• Immediate Reinforcement: More effective, especially for children and animals

• Delayed Reinforcement: Relies on rules or verbal understanding; less effective for young children

Intrinsic vs. Extrinsic Reinforcers

• Intrinsic: Behavior is reinforcing in itself (e.g., swimming for fun)

• Extrinsic: External reward (e.g., getting ice cream for exercising)

Contemporary Theorists

• Jean Piaget: Cognitive development through stages; children actively construct knowledge

• Lev Vygotsky: Culture and social interaction shape development

• Erik Erikson: Psychosocial development across the lifespan

• Albert Bandura: Learning through observation and interaction

• Urie Bronfenbrenner: Development shaped by environmental systems

Piaget's Stages of Cognitive Development

• Sensorimotor (0–2): Learning through senses and actions; object permanence develops

• Preoperational (2–7): Symbolic thinking emerges; thinking is egocentric and illogical

• Concrete Operational (7–11): Logical thinking about concrete objects; conservation understood

• Formal Operational (12+): Abstract and hypothetical thinking develops

Schemas: Mental frameworks for organizing knowledge

• Assimilation: Adding to existing schema

• Accommodation: Modifying or creating new schema

Additional info: These notes synthesize foundational concepts in developmental psychology, suitable for exam preparation and further study.