Developmental Psychology Overview

Vulnerability and Resilience

• This approach examines the complex interplay between individual characteristics and the environment.
• Children may exhibit resilience despite environmental stressors, but similar environments lead to divergent outcomes.
• Children possess inherent protective factors and vulnerabilities that interact with environmental influences.

The Scientific Method in Developmental Psychology

• Developmental psychology uses research to achieve four primary goals:
  • Describe development (what happens).
  • Explain development (why events occur).
  • Predict development (anticipate future events).
  • Influence development (implement interventions).

Studying Age-Related Changes

• Three research designs are used:
  • Cross-sectional: different age groups are studied concurrently.
  • Longitudinal: the same participants are followed over time.
  • Sequential: a combination of cross-sectional and longitudinal designs.

Identifying Relationships Between Variables

• Various methods are employed to study individual differences:
  • Case studies and naturalistic observation.
  • Correlations.
  • Experiments.

Cross-Cultural Research

• Comparing different cultures helps understand universal aspects of development and improve people's lives.
• Key methods include:
  • Ethnography: systematic study of people and cultures.
  • Cross-cultural comparison studies.

Ethical Considerations

• Ethical guidelines protect human and animal participants in research.

The Process of Conception

• Ovulation occurs roughly midway between periods.
• Fertilization happens when sperm and ovum meet in the fallopian tube.
• A zygote forms, a single cell with 46 chromosomes (23 pairs).
• Cell division begins soon after conception.
• Implantation occurs about 10-14 days later; the zygote implants in the uterine wall.

Chromosomes

• Each cell contains 46 chromosomes (23 pairs), with most genetic material located within the nucleus.
• Mitosis is the cell division process where each set duplicates itself.
• 22 pairs are identical in genetic information.
• Sex chromosomes (23rd pair) determine biological sex; females have XX, males have XY.
• Gametes (sperm and ovum) contain only 23 chromosomes each.
• Meiosis is the process where gametes’ chromosomes combine to create 23 pairs at conception.

Chromosomes, DNA and Genes

• Chromosomes are composed of DNA.
• Chromosomes are further divided into genes each of which influences traits or part of a developmental pattern.
• Genetic mapping identifies the location of human genes on chromosomes.

Genotypes, Phenotypes and Genetic Transmission

• Matching chromosomes confer a blended set of instructions.
• Homozygous: identical genes at a locus, e.g., blood type.
• Heterozygous: differing genes at a locus, e.g., hair type.

Gregor Mendel's Principles of Inheritance

• Genotype: set of genetic instructions.
• Phenotype: observed characteristics, arising from the interaction of genotypes and environmental impacts.
• Dominant versus Recessive Genes: one dominant gene's effect outweighs a recessive gene's.
  • Examples of dominant genes: dimples, curly hair, freckles
  • Examples of recessive genes: flat feet, red hair, thin lips
• Polygenic and Multifactorial Transmission: inheritance influenced by numerous genes (skin colour) and factors (height, environment).
• Genomic Imprinting & Mitochondrial Transmission: certain genes are marked, impacting outcomes. Genes on chromosome 15 can cause different syndromes depending on parental origin.
• Twins and Triplets: multiple births increase with fertility drugs.
  • Fraternal twins result from multiple ovum fertilizations.
  • Identical twins arise from a single fertilized ovum's division.

Stages of Prenatal Development

• Germinal Stage: conception to implantation (one week floating, 24/36 hrs, 10-14 day implantation)
• Embryonic Stage: cell differentiation; organogenesis; (heartbeat at 4 wks)
• Foetal Stage: refinement of organ systems; brain and spinal cord develops from neural tube; growth is significant.

Explore key concepts in developmental psychology, including the interplay of vulnerability and resilience in children. Learn about the scientific method applied in this field to describe, explain, predict, and influence developmental stages. Understand the different research designs used to study age-related changes.