developmental psych

• The first year is the most important period of brain growth.
• The germinal period takes place in the first 2 weeks post conception and includes:

  • The creation of fertilized egg (the zygote)
  • Continued cell division
  • Implantation, the attachment of the zygote to the uterine wall
• By one week post conception, cell differentiation has already begun
• The group of cells consists of:

  • An inner mass, the blastocyst, that will become the embryo
  • An outer layer, the trophoblast, which later provides nutrition and support
• Prenatal Development: The Embryonic Period

  • The embryonic period occurs from 2 to 8 weeks post conception
  • Cell differentiation intensifies, support systems for cells form, and organs appear
• Organogenesis is the process of organ formation during the first two months of prenatal development
• Amnion:

  • A bag containing a clear fluid in which the developing embryo floats
  • Provides a shockproof environment and maintains a stable temperature for the embryo
• Umbilical cord:

  • Connects the baby to the placenta
  • Provides nutrients and oxygen to the developing embryo
• Placenta:

  • Tissues in which small blood vessels from the mother and baby intertwine
  • Provides nutrients and oxygen to the developing embryo
• Embryo is quite vulnerable, leading to a high risk of miscarriages
• Time of great vulnerability for the developing embryo
• Fetal period lasts about 7 months
• Pregnancies are divided into three trimesters, each three months long
• Viability, the possibility of surviving outside the womb, occurs at the very end of the second trimester, around 23 to 24 weeks
• Natural selection is the evolutionary process by which individuals best adapted to their environment survive and reproduce
• Adaptive behaviour promotes an organism's survival in its natural habitat
• Evolutionary psychology emphasizes adaptation, reproduction, and "survival of the fittest" in shaping behavior
• Evolutionary Developmental Psychology suggests that an extended childhood period evolved to allow time for brain development and learning complex human societies
• Evolutionary psychology is just one theoretical approach among many
• Genetic influences on behavior have evolved over time and are retained in our DNA
• Genes are short segments of DNA located on chromosomes in the nucleus of human cells
• Humans have approximately 43,000 genes, and genetic expression is influenced by genes' environment
• Every cell in the body has 46 chromosomes in 23 pairs, with the 23rd pair determining sex
• Chromosomes in the zygote are not exact copies of those in the mother's ovaries and father's testes, leading to variability
• Genotype refers to all of a person's genetic material, while phenotype refers to observable characteristics
• Dominant-recessive genes principle states that one gene of a pair can be dominant and override the recessive gene
• Most characteristics are polygenically determined by the interaction of many genes
• Chromosomal abnormalities like Down syndrome and Klinefelter syndrome have specific descriptions, treatments, and incidences
• Gene-linked abnormalities such as cystic fibrosis and diabetes also have descriptions, treatments, and incidences
• Behavior genetics studies the influence of heredity and environment on individual differences in human traits and development
• Twin studies and adoption studies are used to study the influence of heredity on behavior
• Heredity-environment correlations can be passive, evocative, or active, influencing how genes and environment interact
• Shared environmental experiences involve siblings' common experiences, while nonshared experiences are unique to each child
• Shared environment has little impact on children's personality or interests compared to nonshared experiences
• Shared environment has little impact on children's personality or interests
• Parenting or other environmental effects are stronger influences early in development than later
• Maternal IQ is related to higher-quality home environments when the child is very young
• By age 8 or 9 and especially adolescence, children's own IQ becomes more predictive than their mothers' of the quality of their home environment
• Epigenetic view: development results from ongoing interchange between heredity and environment
• Genotype labeled 5-HTTLPR, linked to depression in people with stressful lives