Introduction to Lifespan Developmental Psychology

Introduction to Lifespan Psychology

Overview of the Course

This course explores the field of developmental psychology, focusing on the changes that occur throughout the human lifespan. Key issues include the nature of development, major theoretical perspectives, and the influence of genetics and environment.

What is Development?

Definition and Scope

Development refers to the changes that occur throughout a person's lifespan, including biological, psychological, and social transformations. These changes are influenced by both internal and external factors.

• Physical/Perceptual Development: Changes in the brain, body, and sensory systems.

• Cognitive Development: Changes in thought processes, problem-solving, and language.

• Emotional and Social Development: Changes in emotional regulation, relationships, and moral reasoning.

Periods of Development

Common Breakdown

Development is typically divided into several periods, each characterized by unique challenges and milestones.

• 1. Prenatal period: Conception to birth

• 2. Infancy and toddlerhood: Birth to 2 years

• 3. Early childhood: 2 to 6 years

• 4. Middle childhood: 6 to 11 years

• 5. Adolescence: 11 to 20 years

• 6. Early adulthood

• 7. Middle adulthood

• 8. Late adulthood

When does development end? This is a debated question, as development can be seen as a lifelong process.

Patterns of Development

What Does Development Look Like?

Development can follow different patterns, such as continuous growth, stages, or even regression and recovery. Graphical models often illustrate these patterns.

• Continuous development: Gradual, cumulative change.

• Discontinuous development: Distinct stages or steps.

• Combination: Some aspects may be continuous, others discontinuous.

Key Issues in Developmental Psychology

Nature vs. Nurture

This central debate concerns the relative contributions of genetics (nature) and environment (nurture) to individual differences in development.

• Nature: Genetic inheritance and biological factors.

• Nurture: Environmental influences, such as upbringing and culture.

• Relative contribution: Most modern theories recognize the importance of both.

Continuity vs. Discontinuity

Does development occur gradually (continuity) or in distinct stages (discontinuity)?

• Some types of development are best explained by a combination of both perspectives.

• Example: Language development can show both continuous and stage-like features.

Impact of Context

Development is influenced by multiple layers of context, including genetics, family, community, culture, and historical period.

• Contextual factors can include socioeconomic status, cultural diversity, and historical events.

Key Terms and Concepts

Genotype and Phenotype

• Genotype: The genetic makeup of an individual, inherited from parents.

• Phenotype: Observable characteristics, resulting from the interaction of genotype and environment.

Heritability

Heritability refers to the extent to which individual differences in a trait are due to genetic factors. It is a population-level statistic and does not apply to individuals.

• Heritability is difficult to estimate precisely, especially in humans.

• Genes and environment interact in complex ways.

Canalization

Some traits are highly canalized, meaning they are robust to environmental variation and develop similarly in most individuals unless extreme conditions occur.

• Example: Basic motor skills in infants.

Differential Susceptibility

Individuals differ in their sensitivity to environmental influences based on their genotype. The same genetic makeup can lead to different outcomes depending on the environment.

Gene-Environment Co-variation

People often select environments that complement their genetic tendencies, a process known as gene-environment correlation.

• Example: A child genetically predisposed to athleticism may seek out sports activities.

Epigenetics

Epigenetic mechanisms, such as DNA methylation, can modify gene expression without changing the DNA sequence. These changes can be influenced by environmental factors and may complicate heritability estimates.

Risks and Resilience in Development

Risks to Development

• Physiological risks: Genetic disorders, prenatal exposure to toxins, etc.

• Environmental/experiential risks: Poverty, trauma, lack of stimulation.

Resilience

Resilience is the ability to adapt positively despite adversity. The same experiences can impact individuals differently, depending on protective factors.

• Predictors of resilience:

  • Personal characteristics (e.g., temperament, intelligence)

  • Warm parental relationships

  • Strong relationships outside the family

  • Community resources and opportunities

Dominant Theory: Lifespan Perspective

Key Features

• Lifelong: Development occurs across the entire lifespan.

• Multidimensional and multidirectional: Affected by biological, psychological, and social factors; can involve both gains and losses.

• Plasticity: Capacity for change exists at all ages.

• Influenced by multiple forces: Age, history, culture, and non-normative events.

Summary Table: Key Issues in Developmental Psychology

Issue	Description	Example
Nature vs. Nurture	Genetic vs. environmental influences	Language acquisition, intelligence
Continuity vs. Discontinuity	Gradual change vs. stages	Motor skill development, cognitive stages
Stability vs. Plasticity	Persistence of traits vs. capacity for change	Personality, intelligence
Context	Influence of environment and culture	Socioeconomic status, cultural values

Homework and Preparation

• Enter important dates in your calendar.

• Purchase the required textbook if you have not already done so.

• Read Chapter 1 before the next class.

• Review today's notes and clarify any questions.