New Recording 54

Developmental Psychology Overview

• Developmental psychology studies the physical, cognitive, and socio-emotional changes from conception to the end of life.

• Early focus was on early life environments, but the modern approach includes a lifespan perspective, looking at growth through all life stages.

Research Methods in Developmental Psychology

Cross-Sectional Design

• Examines multiple individuals from different age groups at one time point.

• Example: Measuring working memory capacity in 20-year-olds, 40-year-olds, and 60-year-olds by comparing their performance.

• Limitations:

  • No random assignment to age groups, making it impossible to prove causation.

  • Vulnerable to cohort effects, where differences may be due to shared experiences rather than age.

Longitudinal Design

• Follows the same participants over an extended period.

• Solves cohort effects by studying the same group over time (e.g., measuring 20-year-olds and revisiting them at 60).

• Limitations:

  • Very time-consuming and labor-intensive.

  • Attrition: Participants may drop out of the study, influencing results based on who stays.

Nature vs. Nurture Debate

• Nature refers to biological inheritance (genetics, eye color, brain structure).

• Nurture encompasses environmental and social experiences shaping behavior and attitudes (parenting, culture).

• Both play critical roles in brain development and cognitive processes.

Brain Development in Infancy

• Infants are born with a high number of neurons but lack connections, forming approximately 2 million synapses per second in early years.

• Synaptic Pruning: Unused connections are cut, allowing the brain to adapt according to experiences.

• Experience shapes development, influencing which synapses are maintained.

Language Development

• Infants can initially discriminate sounds from all languages, but pruning leads to specialization based on exposure (e.g., English vs. Japanese sounds).

Understanding Infants' Knowledge

Preferential Looking Task

• Infants look longer at novel or surprising events, indicating they have some expectations about their environment (e.g., understanding that objects don't just disappear).

Understanding of Morality in Infants

• Helper vs. Hinderer Experiment: Infants show preferences for helpful individuals over unhelpful ones, suggesting innate moral understanding.

Interaction of Nature and Nurture in Development

• Language Example: Humans have innate potential for language but require environmental exposure during a critical developmental window. Lack of exposure can hinder language acquisition (e.g., Genie case).

• Reflexes: Many automatic reflexes are seen in infants but are influenced by experiences (e.g., writing reflex in cats vs. environmental exposure).

Prenatal Development Stages

Germinal Period (Weeks 1-2)

• Conception occurs, forming a zygote.

Embryonic Period (Weeks 3-8)

• Major structures and organs take shape, including the formation of the heart and neural tube.

Fetal Period (Week 9 to Birth)

• Growth and maturation of organs, significant brain development, and refinement of movements.

Teratogens: Risks to Fetal Development

• Teratogens are agents that can disrupt development, causing birth defects. Examples include:

  • Nicotine: Linked to physical deficits.

  • Alcohol: Can lead to learning difficulties (Fetal Alcohol Spectrum Disorders).

  • Zika Virus: Risk of microcephaly and cognitive impairments.

  • STIs: Such as gonorrhea causing birth defects.

Cognitive Development According to Piaget

Sensory-Motor Stage (Birth to 2 Years)

• Characterized by reflexive behaviors and lack of abstract representation. Key concept: Object Permanence (understanding that objects exist when out of sight).

Preoperational Stage (2 to 7 Years)

• Symbolic thinking emerges; children engage in pretend play but face limitations such as egocentrism (difficulty seeing others' perspectives) and centration (fixation on one aspect of a situation).

  • Example: Children struggle with tasks demonstrating acknowledgment of different views.

Summary

• Development is shaped by a complex interaction between biological and environmental factors throughout life; understanding this interaction is crucial in psychology.