Developmental psychology

• Developmental psychology deals with the processes of human changes from conception to death
• Theories


  Tools used by developmental psychologists in describing, explaining, and optimizing (raising our consciousness of life issues)
• Theories


  • Clarify the way and manner people change
  • Outline different stages and domains of human development
• Understanding the process of human development equips us better to:

  1. Identify when and how cognitive, affective and motor development from pre-natal stage to old age develop and change

  2. Understand the factors affecting developmental changes and influencing changes

  3. Identify the orderliness and sequential nature of human development

  4. Identify potential challenges in human development

  5. Provide timely interventions to challenges that may occur at any stage of development
• Prenatal development


  A time of remarkable change that helps set the stage for a child's future development
• Germinal stage


  1. Conception to 2 weeks

  2. Fertilized egg (zygote) makes journey down fallopian tube to uterus

  3. Cell division begins 24-36 hours after conception

  4. Zygote goes through cell (chromosomes) reduction (meiosis) to 23 from 46

  5. Zygote divides into two cells, then four, eight, sixteen, etc.

  6. Less than half of all zygotes survive beyond two weeks of fertilization

  7. Female cells contain X chromosome, male has X and Y
• Blastocyst


  Mass of cells that develops into different structures in the body: ectoderm (skin and nervous system), endoderm (digestive and respiratory systems), mesoderm (muscle and skeletal systems)
• Implantation


  1. Blastocyst attaches to uterine wall

  2. Nutrients carried to new organism and waste taken away via placenta

  3. Successful implantation causes hormonal changes, halts menstrual cycle, and other physical changes in mother
• Embryonic stage


  1. 3 to 8 weeks

  2. Neural tube forms and develops into central nervous system, spinal cord and brain

  3. Head, eyes, nose, ears, mouth begin to form

  4. Blood vessel that will become heart starts to pulse

  5. Arm and leg buds appear

  6. All basic organs and parts except sex organs developed by 8 weeks
• Fetal stage


  1. 9 weeks to birth

  2. First trimester: Body systems and structures continue to develop, brain and neurons form, sex organs start to differentiate

  3. Second trimester: Heartbeat grows stronger, body systems further develop

  4. Third trimester: Fetus continues to develop, put on weight, prepare for life outside womb, lungs begin to expand and contract
• Psalm 139:13-18: 'God knew me thoroughly, saw me when I was in the womb, and ordained all my days before they came to be'
• Ecclesiastes 11:5: 'We do not know the work of God who makes everything'
• Good prenatal care


  Essential to development and growth
• Developing child


  • Most at risk during the first three months of development
  • This is a time most mothers are unaware that they are pregnant
• 10% of all birth defects are caused by a prenatal exposure or teratogen
• Teratogens


  Factors that can contribute to birth defects including some maternal diseases, drugs, alcohol, stress, environmental and occupational exposures
• Birth defects caused by teratogens are potentially preventable
• Some Teratogens


  • Genetic Problems
  • Infectious Diseases
  • Medications
  • Maternal Psychoactive Substance use
  • Nutrition/Maternal diet
  • Age of the mother
  • Exposure to radiation
  • Poverty
  • Stress
• Genetic Problems


  Certain genetic problems that impact the growth of a developing child in the womb
• Genetic Problems


  • Down Syndrome
  • Gene diseases (e.g. sickle-cell anemia, cystic fibrosis, Tay-Sachs disease)
  • Sex Chromosome Abnormalities (e.g. Klinefelter syndrome, Fragile X syndrome, Turner syndrome, Super Male syndrome, Poly-X syndrome)
• Genotype


  The genes that a person inherited
• Phenotype


  The actual expression of the genes e.g. physical traits such as height and color of the eyes and also nonphysical traits such as personality
• Infectious Diseases


  • Rubella (German measles)
  • Syphilis
  • Toxoplasma (parasite found in cat feces, contaminated food, uncooked meat)
  • Varicella zoster (chicken pox)
• Fetal alcohol syndrome


  Disorders associated with maternal alcohol use including heart defects, body malformations, and intellectual disability
• Nutrition/Maternal diet


  Deficiency of proper nutrition leads to abnormal development including still birth, premature birth, intellectual and physical retardation
• Normal child bearing age for mothers

  Between 20 and 35 years
• Children born after the age of 40


  • Have higher proportion of retardation, prolonged labor and physical defects
• Exposure to radiation


  Excessive exposure to infrared radiation (x-ray) can severely cause malfunction of the brain and deformation
• Poverty


  May cause expectant mother to deny herself proper and nutritive diet, adequate medical diagnosis or professional assistance which consequently impact the development of the fetus
• Stress


  Mothers who go through stress due to economic problems or social disruptions are said to have malnourished children right from the womb
• Factors influencing level of prenatal risks

  • Exposure time (body structures are most vulnerable when they are forming)
  • Extent of exposure (some substances are not harmful except a certain level is reached)
  • Genetics (some mothers may be more resistant to teratogenic effects)
  • Gender of the child (more males than females are likely to experience damage)
• Natural Observation


  Observing the behavior of a child in the natural setting or using the responses of the child to assess the changes or developmental patterns, can be controlled or uncontrolled
• Interview


  Face to face interaction between the Psychologist and the child under investigation, can be structured or unstructured
• Cross-sectional studies


  Focusing on characteristics and behavioral patterns of groups of people of different ages
• Advantages of Cross-sectional studies


  • Quick, specific behavioral patterns can be studied in details, less expensive, reduces attrition of participants
• Disadvantages of Cross-sectional studies


  • Selection of participants of different ages who share same study characteristics could be difficult, changes that occur may be due to ageing process or experience rather than age
• Case study


  Focuses upon a single individual rather than a group of subjects
• Survey


  Systematic presentation of questions to elicit responses from study group
• Experimentation


  Manipulation of variables, usually contains more than one group of participants
• Longitudinal study


  Investigation conducted over a long period of time (years) on the same study group