Karteikarten
Stress
Karten in diesem Stapel (34)
- 1Where are individual differences seen in stress? What happens in individuals with too little response? What happens with individuals with too much response?Great variation in acute and long-term stress responses.
These are individuals who don't deal with dangerous situations and do not get ready enough to fight or flee, therefore often get injured or die.
These are individuals who cannot cope with fairly normal situations for example getting stressed over a birthday party. - 2What happens to people who fare badly to stressors?They often show long-term disruptive outcomes such as PTSD and psychopathy. Despite similar stressful situations, people who do not fare badly show resilience.
- 3What is the major question within this topic?What individual differences lie behind vulnerability and resilience?
- 4What are the 2 factors found to affect vulnerability and resilience to stress?Predispositions such as genetic predispositions and environment and environment alone.
- 5What 4 genetic predispositions can affect stress levels?1. Bodily health and fitness.
2. Feelings for control/predictability of the environment (out of control increases stress).
3. Individual's actual mastery/control over then environment (often determined by factors such as intelligence, beauty, wealth)
4. Brain health. - 6What 4 environmental influences are there on predisposition?1. Environmental enrichment (higher decreases vulnerability).
2. Parental experiences in early life (maternal engagement).
3. Richness of social buffering (people who feel supported feel less stressed).
4. Education. - 7When measuring environmental influence during or post-stress, what must we consider? What is another word for stress response?The two stressors to be similar and evaluate what in an individual's environment/nature causes differences in individuals' stress response. For example, quantity and quality of social buffering.
Fight/flight response. - 8What happens during the fight/flight response (2 things)?1. An acute release of adrenaline and noradrenaline.
2. Release of cortisol. - 9What 4 effects does the release of these substances have?1. Increased arousal.
2. Increased muscle tone.
3. Increased heart rate and blood pressure.
4. Increased catabolism of fat and glucose reserves (catabolism is the set of metabolic pathways that breaks down molecules into smaller units to release energy). - 10Why does this anatomical activity occur?In order to prepare the human/animal body for fight or flight action to deal with situations and survive.
- 11What is the HPA axis?It is the hypothalamic-pituitary-adrenal axis and is used to refer to interactions between the hypothalamus, pituitary gland and adrenal gland that controls reactions to stress.
- 12What is the Diathesis-Stress Model?The prevailing model of vulnerability to stress which states genetic inheritance and both previous/recent experiences result in predisposition of stress.
Predispositions x environment interactions. - 13What is diathesis? What do common stressors include?The tendency to suffer from a condition.
Abuse, neglect, divorce and death of loved ones. - 14What does the Diathesis-Stress model state?High vulnerability followed by stress is what causes poor responses such as depression, alcoholism and PTSD.
- 15How are events that are stressors determined? What must be noted?1. How life threatening.
2. How unpredictable/uncontrollable.
That levels are subjective to each individual. - 16What two brain areas are strongly involved in anxiety?1. Hippocampus
2. Amygdala - 17What do the hippocampus and amygdala both have high densities of? What do genetics and environment influence the volume/development of?Cortisol receptors which are released during stress scenarios.
Hippocampus which influences vulnerability to stress. - 18Who was the main researcher of post-natal stress? What study did he conduct with rats? What are the 3 key results?Meany 2001.
He investigated the effects of handling rats in the first few years of life.
1. Handled rats are less fearful, anxious and have lower HPA axis responses to stress.
2. Handled rats have less ageing in their hippocampus.
3. Handled rats are less resistant to an experimentally-induced brain infection, due to lower stress response. - 19What was Meany's 2nd study? What are the 3 key results?2001. Measured the effects of maternal separation in rats once a day for 3 hours from day 2-14.
1. Maternal separation showed stronger HPA activation to acute stress.
2. Changes in maternally-separated rats was found in the cortical receptor binding in the hippocampus and hypothalamus.
3. Rats separated displayed more anxiety and fearful behaviour as adults in ways such as reduced feeding in novel scenes and increased startle. - 20What was Meany's 3rd study?2001.
Investigated maternal style and the role of oxytocin in rats. After observing maternal styles such as frequency of maternal grooming in the 1st week, the study found that frequency of grooming positively correlated with the magnitude of corticalsterone (animal version of cortisol) responses later. More maternal grooming led to lower adult stress response also led to less anxious adults again measured by decreased startling, increased exploration and eating in novel scenarios. The hippocampus in high-licked offspring led to more synapses growing there. - 21Who conducted a maternal support study in human children? What did they investigate? What was the study? Result: Interpretation:Luby 2012.
Whether maternal support in early childhood predicts larger hippocampal volume at school age using MRI scanning.
Involved observing parent and child in a stressful waiting event; the child had to wait to open a present.
Stronger maternal support at a young age predicted larger hippocampal volume at school age.
Maternal influences help shape hippocampi and perhaps reduce stress response. - 22What did Kikusui et al 2006 find? What is this phenomenon known as?That for social mammals such as rats, monkeys and humans, mingling with members of your own species improves recovery from stressful experience, but not just own species; pet dogs can reduce owner's stress.
Social buffering. - 23What are humans known to do under stress? What does social buffering reduce the release of?Affiliate (attach or connect to another person).
Cortisol. - 24Examples of how social buffering reduces stress. (3 studies)King et al 1998 found that post-deployment, social support significantly reduced development of PTSD in Vietnam war veterans of both genders.
Hyman et al 2003 found that social support significantly reduced development of PTSD in survivors of childhood sexual abuse.
Pietrzak et al 2010 found that lower post-deployment social support was associated with increased PTSD. - 25How does oxytocin reduce stress? What are the 3 steps and what does oxytocin do?By having an inhibitory effect at the 3 stages of the HPA axis.
Oxytocin acts on the adrenal gland to inhibit cortical secretion.
Oxytocin inhibits ACTh release from the pituitary gland.
Central oxytocin inhibits CRF activation. - 26How do individual differences in oxytocin develop? What can be concluded from this?More social contact (induces the release of oxytocin) and good gene receptors which allow efficient response to oxytocin.
That both genetic and environment influence oxytocin-mediated stress reduction. - 27Who investigated genetic variation in relation to stress reactivity? Result:Rodrigues et al 2009.
Found that people with a GG genotype showed better empathy and lower stress response in a lab as well as lower self-reported general stress levels. - 28Who conducted a meta-analysis on PTSD studies? What was found? Interpretation:Smith 2005.
He conducted a meta-analysis of 13 studies that showed that PTSD patients had 7% smaller left hippocampal volume and 7% smaller right hippocampal volume compared to controls.
Increased hippocampal volume helps alleviate PTSD by allowing them to make better context-specific predictions and have locus of control (control of events affecting them). - 29What question did this study lead to? Who investigated this? What did they do? Results: Interpretation:Is a small hippocampal volume a predisposing factor to stress or does stress reduce hippocampal volume?
Gilbertson et al 2002.
Used twins to investigate whether small hippocampus predisposes stress or stress reduces hippocampus size. 4 groups; men who went to war and have PTSD, their twin who didn't go to war, men who went to war but didn't get PTSD and their twin who didn't go to war.
Twin with PTSD had a smaller hippocampus to those who don't have PTSD, war-unexposed twin of PTSD twin also had a smaller hippocampus, not greatly different from the PTSD twin's size. The set of twins with the PTSD twin had smaller hippocampal volume compared to the no-PTSD twins.
War stress did not shrink hippocampus in PTSD sufferer.
A strong negative correlation was found between PTSD severity and their hippocampal volumes.
A strong negative correlation was also found between PTSD severity of war-exposed twin and their twin brother's hippocampal volume who didn't go to war. - 30What is an unresolved issue that still remains?Is hippocampus size heritable, environmental, or both?
- 31Evidence for stress shrinking the hippocampus. What 4 effects has stress been found to have on the hippocampus?1. It decreases the rate of neurogenesis.
2. It decreases hippocampal volume and cell body size.
3. It decreases the spines on dendrites.
4. Retraction and de-branching of dendrites of neurons.
(All above have been shown in animals and are believed to apply to humans.) - 32Who investigated chronic life stress in relation to grey matter volume in the hippocampus? What was done? Results: Interpretation:Gianros et al 2007.
48 post-menopausal women filled out a perceived-stress scale and Beck depression inventory. Brain imaging was conducted. Several assessments over a 20-year time frame.
Average stress scores correlated with volumes in different brain regions with high scores having strong correlations with hippocampal volume and right orbitofrontal volume.
Stress does alter hippocampal volume but does not rule out influence of pre-existing volume.
A longitudinal study would be needed to determine this issue. - 33More evidence for stress shrinking hippocampus?Lee et al 2009.
Investigated the effect of stress on rats. 10 controls, 10 stressed rats. They stressed rats by restraining them for 6 hours a day for 3 weeks. They conducted MRIs before and after.
3% shrinkage in hippocampal volume after just 3 weeks.
Issue: generalisability, does it apply to humans? - 34More evidence for stress shrinks the hippocampus?Carrion et al 2007.
Measured the correlation between PTSD and hippocampal volume change.
Hippocampal volumes shrink later if PTSD scores are high now, therefore small hippocampal volume does not predispose PTSD.
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- Degree Differential Term One Karteikarten am Stress, erstellt von kat.bridgman am 03/05/2015.
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