Human Development and Psychological Theories and Stages

Overview of Human Development

• Human Development Domains: Consists of three primary areas: physical (body and brain changes), cognitive (thinking and problem-solving), and psychosocial (interactions and self-understanding).

• Key Figures:

  • Piaget: Swiss psychologist known for the theory of cognitive development.

  • Erik Erikson: Focused on the psychosocial development of human beings.

  • Lev Vygotsky: Noted for social constructivism and the role of social interaction in learning.

Periods of Development

• Prenatal: From conception to birth.

• Infancy: Birth to $2\,years$.

• Early Childhood: $3$ to $5\,years$.

• Middle Childhood: $6$ to $11\,years$.

• Adolescence: $12$ to $18\,years$.

• Young Adulthood: $18$ to $40\,years$.

• Middle Adulthood: $40$ to $65\,years$.

• Late Adulthood: $65+\,years$.

Prenatal and Infant Physical Growth

• Prenatal Milestones:

  • Zygote (0-4 weeks): Less than $\frac{1}{10}\,inch$ long.

  • Embryo (8 weeks): About $0.6\,inch$ long; face and brain forming.

  • Fetus (12 weeks): About $2\,inches$ long, weighs $0.5\,ounce$.

• Infant Growth:

  • Newborns typically weigh $5$ to $10\,pounds$ and are $18$ to $22\,inches$ long.

  • Babies grow roughly $1\,inch$ per month in the first year.

  • By age $2$, weight is roughly $26$ to $32\,pounds$ and height is $32$ to $35\,inches$.

• Episodic Growth: Development occurs at unique paces; some infants experience rapid growth spurts while others grow more slowly.

Piaget’s Four Stages of Cognitive Development

• Sensorimotor Stage (Birth to $2\,years$):

  • Learning via senses and motor actions.

  • Object Permanence: Developing the understanding that objects exist even when not visible (typically at $8$ to $12\,months$).

• Preoperational Stage ($2$ to $7\,years$):

  • Symbolic Thinking: Use of pretend play and language.

  • Egocentrism: Difficulty seeing the world from others' perspectives.

  • Lack of Conservation: Inability to recognize that quantity remains the same despite changes in shape.

  • Intuitive Thinking: Relying on intuition over logical reasoning.

• Concrete Operational Stage ($7$ to $11\,years$):

  • Logical thinking about concrete events.

  • Mastery of Conservation, Classification, and Seriation (ordering objects).

• Formal Operational Stage ($12\,years$ and onwards):

  • Capability for abstract thinking, advanced reasoning, and systematic problem-solving.

  • Adolescent Egocentrism: Includes the belief in an "imaginary audience" where the teenager feels constantly observed and judged.

Vygotsky’s Social Constructivism

• Zone of Proximal Development (ZPD): The gap between what a child can do alone and what they can achieve with guidance.

• Scaffolding: The temporary support provided by a more knowledgeable person that is gradually reduced as competence increases.

Erikson’s Psychosocial Stages

• Trust vs. Mistrust (0-1 year): Dependence on caregivers for security.

• Autonomy vs. Shame and Doubt (1-3 years): Developing independence and choice.

• Initiative vs. Guilt (3-6 years): Initiating activities and social play.

• Industry vs. Inferiority (6-12 years): Gaining pride in accomplishments and skills.

• Identity vs. Role Confusion (12-18 years): Exploring roles and forming a sense of self.

• Intimacy vs. Isolation (18-40 years): Establishing deep, meaningful relationships.

• Generativity vs. Stagnation (40-65 years): Contributing to society and the next generation.

• Integrity vs. Despair (65+ years): Reflecting on life with satisfaction or regret.