Prenatal Development & Theories (PSY 112 Week 2 - Jan 2024) PDF

WEEK 2: PRENATAL DEVELOPMENT & THEORIES OF DEVELOPMENT outline the stages of prenatal development describe the common types of teratogens differentiate the main theories of human development LIFE-SPAN DEVELOPMENT PRENATAL DEVELOPMENT THE COURSE OF PRENATAL DEVELOPMENT Begins with fertiliza...

WEEK 2: PRENATAL DEVELOPMENT & THEORIES OF DEVELOPMENT outline the stages of prenatal development describe the common types of teratogens differentiate the main theories of human development LIFE-SPAN DEVELOPMENT PRENATAL DEVELOPMENT THE COURSE OF PRENATAL DEVELOPMENT Begins with fertilization and ends with birth (266-280 days; 38-40 weeks) GERMINAL EMBRYONIC FETAL THE COURSE OF PRENATAL DEVELOPMENT GERMINAL EMBRYONIC FETAL Germinal period (first 2 weeks after conception) (1) creation of fertilized egg (zygote), (2) cell division (mitosis), and (3) attachment of zygote to uterine wall Fertilization: Ovum & sperm unite (23 + 23 = total 46 chromosomes; i.e., zygote) Twins: Monozygotic vs. Dizygotic (see next slide) Rapid cell division occurs 1 week after conception: o Differentiation: Specialization of cells to perform various tasks; e.g., skin cells, heart cells, etc. o Group of cells now a blastocyst: inner mass of cells (later embryo) + trophoblast (outer layer of cells that later provides embryo with nutrition/support) Implantation: Attachment of zygote to uterine wall (11-15 days after conception) THE COURSE OF PRENATAL DEVELOPMENT (Germinal Period) / Monozygotic twins 1 zygote splits into 2 embryos Genetically identical 2 zygotes are / Dizygotic twins formed Genetically dissimilar THE COURSE OF PRENATAL DEVELOPMENT (Germinal Period) THE COURSE OF PRENATAL DEVELOPMENT GERMINAL EMBRYONIC FETAL Embryonic period (2 to 8 weeks after conception) Begins when blastocyst attaches to uterine wall (now called embryo) Cell differentiation intensifies, support systems form, and organs appear (most organs present by end of embryonic period) Embryo has 3 primary germ layers: o Endoderm – Inner layer; develops into digestive & respiratory systems o Mesoderm – Middle layer; becomes the bones, muscles, & circulatory, excretory, & reproductive systems o Ectoderm – Outer layer; becomes the nervous system & brain, sensory receptors, skin parts (hair & nails) Life-support systems: o Amnion – Sac with clear fluid (embryo floats inside); amniotic fluid is shockproof o Umbilical cord – Contains 2 arteries & 1 vein; connects baby to placenta o Placenta – Disk-shaped group of tissues where small blood vessels from mother intertwine but do not join Organogenesis: Organ formation during first 2 months of prenatal development THE COURSE OF PRENATAL DEVELOPMENT (Embryonic Period) From Zygote to Blastocyst to Embryo Source: https://opentextbc.ca/biology/chapter/13-2-development-and-organogenesis/ THE COURSE OF PRENATAL DEVELOPMENT (Embryonic Period) From Zygote to Blastocyst to Embryo THE COURSE OF PRENATAL DEVELOPMENT GERMINAL EMBRYONIC FETAL Fetal period (begins from 2 months after conception until birth) Dramatic growth and development continue Fetus viable at end of 2nd trimester (24 to 25 weeks after conception) NOTE: Prenatal development divided into 3 trimesters (3-month periods) o Germinal & embryonic periods → occur within 1st trimester o Fetal period → begins toward end of 1st trimester; continues through the 2nd and 3rd trimesters Fetus is full term at 38 weeks o Born < 38 weeks = preterm (may require support to survive) o If very premature and low birth weight, potential long-term problems o Miscarriages/spontaneous abortions → most likely in first 3 months (usually due to genetic defect)  1st trimester (Germinal and Embryonic) (Fetal) 2nd trimester (Fetal) 3rd trimester (Fetal) TERATOGENS Embryo receives nourishment from mother → vulnerable to hazards (diseases, toxins) Critical periods Times during which certain environmental influences may impact infant development Especially when major organs are forming: o Limbs (3-8 weeks) Prenatal hazards o Heart’s structure (2-6 weeks) Teratogens: o Central nervous system (2-5 weeks) o Agents/factors that can cause birth o Eyes (3-8 weeks) defects or negatively alter cognitive and o Teeth, mouth roof (7-12 weeks) behavioural developmental outcomes TERATOGENS Timing of teratogenic effects on prenatal development TERATOGENS THEORIES OF DEVELOPMENT  Psychoanalytic Perspective Conflicts ◦ biological drives/instincts ◦ social expectations F__________ & Erik Erikson Emphasis on unique life history This Photo by Unknown Author is licensed under CC BY-SA  ◼ largest portion of the mind ◼ unconscious, present at birth I_ ◼ source of biological needs/desires ◼ conscious, rational part of FREUD’S mind THREE PARTS E__ ◼ emerges in early infancy ◼ redirects id impulses OF THE acceptably PERSONALITY ◼ the conscience S____ ◼ develops from ages 3 to 6 ___ from interactions with caregivers Freud’s Psychosexual Stages Family Life This Photo by Unknown Author is licensed under CC BY-SA-NC Erikson’s Psychosocial Stages This Photo by Unknown Author is licensed under CC BY-SA  Behaviorism & Stimulus– _________________conditioning Social Learning response Reinforcers ________________ and ◦ PAVLOV conditioning punishments ◦ SKINNER Social learning Modeling ◦ BANDURA Cognitive-Developmental Theory Piaget ◦ Active construction of knowledge. ◦ Adaptation to environment is made in order to achieve equilibrium. ◦ All children move through 4 broad stages. Piaget’s Stages S__________ P__________ C________ operational F_______ operational Object permanence Symbolic representations Conservation Hypothetical thinking Animism LIFESPAN DEVELOPMENT Information-Processing Theory Explain how the mind Development seen as manages/manipulates/monitor continuously changing, not information formal stages Developmental Cognitive Neuroscience Studies relationships between ◦ changes in the brain ◦ development of cognition, behavior Brings together researchers from ◦ psychology ◦ biology ◦ neuroscience ◦ medicine Ethology & Evolutionary developmental psychology Emphasizes genetically determined survival behaviors presumed to have evolved through natural selection - critical period vs. sensitive period IMPRINTING: Innate learning that involves attachment to first moving object  Critical Period & Sensitive Period - Crucial time when a given Somewhat ideal/optimal time when a event, or its absence, has person is particularly responsive to certain a specific impact on kinds of experiences development less defined boundaries - Development will not take place if not introduced This Photo by Unknown Author is licensed under CC BY-SA-NC Vygotsky’s Sociocultural Theory ◦ Values, beliefs, customs, skills (culture) are transmitted to new generation ◦ Social interaction essentials: ◦ Cooperative dialogues with more knowledgeable members of society ◦ Contextual factors affect children’s This Photo by Unknown Author is licensed under CC BY-SA development This Photo by Unknown Author is licensed under CC BY-SA-NC LIFE SPAN DEVELOPMENT  Vygotsky’s view: “…what a child can do with assistance today she will be able to do by herself tomorrow.” (Vygotsky, 1978)  Contrast with Piaget: “Every time we teach a child something, we keep him from inventing it himself. On the other hand, that which we allow him to discover for himself will remain with him visible for the rest of his life.” (Piaget, in Piers, 1972) LIFESPAN DEVELOPMENT  Bioecological Systems Theory M________________ ◦ Settings that influence an individual directly through immediate participation M________________ ◦ System of relationships among the individual’s microsystem E_______________ ◦ Social settings which can affect an individual but the individual does not participate directly M______________ ◦ Culture and subculture of individual This Photo by Unknown Author is licensed under CC BY-SA-NC Comparison of Theories and Issues in Life-Span Development 1 - 35 Comparison of Theories and Issues in Life-Span Development (Cont’d) 1 - 36 See you next week!