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Chapter 2

How We Grow: Developmental Psychology

#Developmental Psychology#Libido#Psychosocial Crisis#Cognitive Development#Assimilation & Accommodation#Morality

Chapter 2: How We Grow - Developmental Psychology

Developmental Psychology is the study of the processes of change throughout the human lifespan. We don’t just get older; we mature through complex psychological stages.


1. Theories of Personality and Social Development

(1) Freud’s Psychosexual Development Stages

Freud defined human mental energy as ==Libido== and divided development stages based on where this energy is concentrated.

  • Oral → Anal → Phallic → Latent → Genital
  • He believed that if needs are not properly met at each stage, “fixation” can occur in adulthood.

(2) Erikson’s Psychosocial Development Stages

Expanding on Freud’s theory, Erikson proposed an 8-stage model spanning the entire life. Each stage involves a ==Psychosocial Crisis== to be resolved.

  • Infancy: Trust vs. Mistrust
  • Adolescence: Identity vs. Role Confusion (The most critical stage)
  • Early Adulthood: Intimacy vs. Isolation

2. Development of Intelligence and Thought: Jean Piaget

Piaget observed that the way children understand the world is fundamentally different from that of adults.

Development StageKey FeaturesCore Concept
SensorimotorExploring the world through senses/motorObject Permanence
PreoperationalBeginning of language use, egocentrismSymbolic Play
Concrete OperationalBeginning of logical thinkingConcept of ==Conservation==
Formal OperationalAbstract and hypothetical thinkingDeductive Reasoning

Mechanisms of Knowledge Construction

  • Assimilation: Fitting new information into existing frameworks (Schemas).
  • Accommodation: Modifying existing frameworks to fit new information.

3. Moral Development: Lawrence Kohlberg

Human moral judgment evolves from “Avoiding Punishment” to “Social Contract” and eventually to “Universal Ethical Principles.”


Key Checklist

  • In Erikson’s 8 stages, which period focuses on forming an identity and asking “Who am I?” (Answer: Adolescence)
  • In Piaget’s theory, what is the process of taking in new information to fit existing cognitive structures? (Answer: Assimilation)
  • What is the concept of understanding that the essential quantity of an object remains the same even if its appearance changes? (Answer: Conservation)