Psychology BLoA Flashcards
Effects of Acetylcholine in brain
Martinez and Kesner (1991)
- Rats in the maze -3 groups, 2 drugged one controlled one blocked the other delayed the reuptake
- Rats with the delayed reuptake drug did better
- Acetylcholine is a key factor in creating memory and development of memory formations Study shows that ACh is important in memory since the rats showed different memory capacity depending on ACh levels.
- Laboratory experiment: ACh is one factor that address memory but the neurobiology of memory is very complex
Bouchard et al (1990)
56 Twin study with interviews and intelligence tests
Cross-cultural (different countries)
Correlational!
88% MZA : reared apart
69% MZT : together
Mostly genetic inheritance/disposition
-Concordance rates decreased as family relationships became more distant
Conclusion: environmental factors do play a role in development of intelligence however it is 70% genetic and 30% environmental
- Largest sample of twins
- however contact with twins
Baumgartner et al (2008)
Participants played a trust game: prisoner’s dilemma. Nasal oxytocin or placebo fMRI 49 participants Placebo: likely to show less trust after betrayal Oxytocin: similar rates fMRIs: decrease in response of amygdala (involved in emotional processing that has many oxytocin receptors). Associated with learning, memory and plays a role in reward-related responses and learning to trust. Giving oxytocin does not reflect the natural physiological processes. The function of oxytocin is very complex and it is too simplistic to say it is the “trust hormone”
Stimulating Environments
These types of environments encourage and contribute to dendritic branching
- Rats having done more exercise Moreover their performance on learning exams was better
- The cortex gets even thicker if rats are placed in company of other rats (part of a stimulating environment)
Fehr et al (2005)
- Participants were 178 male college students -played investment game
- Those given Oxytocin were investing 17% more than the placebo group this study cannot be generalized as it is males and college students Points to consider:
- Trust is influenced by many other factors
Oxytocin - Love Hormone
- Produced by the hypothalamus after being stimulated by the pituitary gland
- Effective child labour (promotion of contractions)
- Breast feeding releases oxytocin
- This release creates the feeling of content, reduces anxiety and increases feelings of security
- Oxytocin reduces activity in the amygdalae (processing of memory, decision-making and emotional reactions)
- Restore trust and be forgiving (relationships)
- Treatment for Autism
Ditzen (2009) Couple study- snorting intra nasally oxytocin
-47 adult heterosexual couples -two groups: placebo and oxytocin intra-nasally
-Couples talked about topics that caused conflict
-Reduced levels of stress hormone cortisol (in the saliva)
Conclusion: Oxytocin reduced stress and promotes feelings of empathy
Functions of Hormones human behaviour
-Produced by glands that make up the endocrine(nervous) system
-Conveyed by blood -Will take longer to produce changes in behaviours than neurotransmitters -a chemical can be both a hormone and neurotransmitter
Differences:
-Hormones flow through the blood so they take a while to kick in to action
Human behavior is to some extent genetically based**
Genetic inheritance should be seen as genetic predisposition which can be affected by environmental factors- twin studies
Nature and Nurture
The environment can influence our brain/nervous system Seed Metaphor we need good/healthy things in order to grow properly Our body/brain interact with our environment -Optimal condition in our surroundings will allow our body/brain to develop in the best way possible (education, healthy food, not too much stress, good sleep etc)
Education key stimulating factor*
Jacobs et al (1993) Observed that people with extensive academic education had longer and more widely branched dendrites than people with leas formal education
**Did education cause the wider dendrites or wider dendrites cause people to become more interested in education
Rosenzweig & Bennet (1972)
Researching how different environments affect the Rat’s brains -Enriched environment: Rats with stimulatinh environments (toys and ramps) -Stimulating environments: Rats had simple toys -Deprived environment:simple cage with no toys -Rats spent 1~2 months in these cages -Sacrificing the rats- Post Mortem autopsies revealed that rats woth enriched environments had a thicker cortex in the frontal lobe (the oart responsible for thinking planning and decision making -Controlled laboratory trial so it is possible to establish a cause and effect relationship -Animals are used -Shows how the brain can change and adapt to new situations. -The brain can be affected by environmental factors and social stimulation
Predisposition
There will be the need of a particular environmental stimuli for the behaviours to manifest
There will be the need of a particular environmental stimuli for the behaviours to manifest
Cannot establish a cause and effect as they cannot be measure directly brain chemistry versus affecting of our behaviour
Diathesis - Stress Model
Our behaviour is influenced by both nature and nurture :) (Diathesis: Nature - Stress: Nurture) Predispositions and triggers 1. Psychological (the way we think) 2. Environment (nutrition, school etc) 3. Biological factors (genetic makeup)
A good model as it considers several different factors as influential
