Neuropsychobiological Issues Flashcards
Epigenetics
Process by which genetic transcription is influenced by environmental factors. Can be influenced by environmental forces, such as smoking, diet, toxins, pollutants stressful life events, medications or even therapeutic interventions (Yan, 2010). Leave unique epigenetic “signatures” on genes that can be temporary or permanent
Outline the perspectives on the development of aggression
Nativists claim aggression is an innate unchangeable part of us present from birth -> Might be able to re-direct our aggression into something constructive (e.g. sport, business, art) or “mask” (e.g., medication) but we can never get rid of it.
Nurturists claim aggression is learned -> If we can improve the circumstances in which people grow up (e.g. better parenting, tackle poverty, improve education, less violence in the media) then we can have a less violent society.
Interactionists accept that certain level of aggression may be unavoidable, but much can be done to reduce extreme aggression by improving people’s environments.
Outline the FOAD hypothesis
Adverse intrauterine environmental exposures affect a fetus’ development during sensitive periods, increasing the risk of specific diseases in adult life.
Outline the research to develop the FOAD hypothesis
First studies: adverse nutrition prenatally as measured by birth weight increased susceptibility to metabolic syndrome later in life
Subsequent studies: implications extend beyond low birth weight/ malnourished population to other chronic conditions including where babies exposed to prenatal stress
Implications: Essential shift in our understanding of determinants for health with vast implications for healthcare prevention and management
Outline the Fetal programming hypothesis
Proposes these diseases originate through adaptations the fetus makes when exposed to certain intrauterine conditions, may be vascular, metabolic or endocrine but permanently change the function/structure of the body in adult life
What role does the HPA axis play in the Fetal programming hypothesis
Mediating role of the hypothalamic-pituitary-adrenal or HPA axis. Hormones pass through the placenta and influence baby’s own developing hypothalamic regulatory genes -> results in “fetal programming” in utero *Epigenetic mechanism
Outline the stress example of the Fetal programming hypothesis
cortisol crosses the placenta -> Infant HPA axis responds to maternal stress hormones -> Leads to adaptive response from fetus with lasting consequences for behaviour/neurobiology -> Changes in structure of the prefrontal cortex and amygdala and function of neural systems responsible for infant regulation -> Modest evidence optimal caregiving can attenuate negative effects of fetal programming of stress response -> caregiver response and coregulation of infant negative affect is crucial (c.f. Michael Meaney rat study)
Evaluation of the fetal programming hypothesis
Calls for a broader “life-course perspective”
- Study of long-term effects of physical and social exposures during gestation and across the lifespan on chronic disease risk
- Timing of exposure variables, as well as how they interact, is considered vitally important.
outline the bio, psycho and social factors in anxiety
“Bio” – Child’s biological father and paternal grandmother both suffer from Generalised Anxiety Disorder (i.e. possesses genetic predisposition for anxiety)
“Psychological” – Child has highly perfectionistic tendencies
“Social” – Child attends high performing academically geared high school that promotes extreme competitiveness between students and encounters bullying when not performing as well as peers
what is the greatest risk to prenatal development and when
exposure to teratogens during the embryonic period (implantation -> 8 weeks)
outline the prenatal developmental germinal and embryonic periods
- Conception
- Zygote - a fertilised egg
- Germinal period - first twp weels after conception
- Embryonic period - weeks three through eight after conception
- Fetal period - two months after conception until birth
What is a teratogen and what does it’s impact depends on
Any agent that causes a birth defect. The impact depends on dosage and duration of exposure, genetic make up of unborn child and mother, other aspects of environment, timing of exposure (critical periods is organogenesis)
What is a teratogen and what does it’s impact depends on
Any agent that causes a birth defect. The impact depends on dosage and duration of exposure, genetic make-up of unborn child and mother, other aspects of the environment, the timing of exposure (critical periods is organogenesis)
The term Fetal Alcohol Spectrum Disorder (FASD) was coined as an “umbrella” term, as opposed to diagnosis, to encompass the diagnostic categories of:
Fetal Alcohol Syndrome, partial Fetal Alcohol Syndrome, Alcohol-Related Neurodevelopmental Disorder and Alcohol-Related Birth Defects
What is the cause of Fetal Alcohol Spectrum Disorder (FASD)
- When alcohol is consumed during pregnancy, it passes through the placenta and enters the bloodstream of unborn babies.
- This can affect brain development in unborn babies
- Effects not uniform (Not linearly associated with alcohol quantity, Moderated by genetic and environmental variables)