Final Review Flashcards
What are the biological effects and behavioural outcomes of leptin and ghrelin?
Leptin - produced by fat cells, influnecings neurons in hypothalamic regions to reduce blood intake and appetite, increase energy expenditure, inhibit reward-seeking behaviours (satiety)
Ghrelin - produced in gut and acts antagonistically to leptin by stimulating appetite, reducing energy expenditure, enhancing reward-seeking behaviours, and modulating stress responses (hunger)
What are the biological effects and behavioural outcomes of insulin?
Produced by beta cells in pancreas and is responsible for regulating fat and carb metabolism, gets glucose from blood not target cells stored as glycogen, interactions with immune functioning
In the brain, it simulates hormones that reduce food intake
What type of depression is most closely linked to inflammation?
Atypical depression - characterized by increasing eating, sleeping, and tendency towards persistent rejection sensitivity and mood reactivity
What is the biological and behavioural outcomes of testosterone and dehydroepiandrosterone (DHEA)
testosterone - produced in testes and of lesser extent in adrenal glands of males; involved in the sexual differentiation of brain and reproductive system, fundamental in secondary sexual features (muscle, body hair, bone mass), and associated with aggressive, dominant, and sexual behaviours
DHEA - produced in adrenals, gonads, and brain; acts as a anabolic steroid to affect muscle development; behaviourally acts like testosterone
What is the biological effect and behavioural outcomes of estrogens and progesterone?
Estrogen (estradiol) - produced in ovaries and regulates hypothalamic-pituitary-ovarian axis; involved in protein synthesis, GI functioning, coagulation, cholesterol levels and fat depositions, affects bone density; important for maternal behaviour, maintaining cognition, as well as anxiety and stress responses
Progesterone - formed in ovaries; involved in triggering menstruation and maintaining pregnancy; reduces uterine smooth muscle contraction; influences resilience of various tissues; affects maternal behaviours and has anti-anxiety actions
How does the menstruation cycle affect the stress response?
During ovulation women have a spike of hormones including follicle stimulating hormones, lutenziing hormone, and estradiol which promotes changes in both termpature and uterine status.
Following ovulation during the luteal phase there is a slow decrease in leninizeing hormone and an increase in progesterone (anti-anxiety) - also when cortisol levels are generally thought to be the highest
These changes can moderate how one reactions to stressors as well as contribute to their immune changes
- estrogen can attenuate HPA activity and act as a protective factor until menopause
- progesterone is anti-inflammatory
What is the biological effect and behavioural outcome of prolactin?
It is released from the pituitary and the primary function is milk production and maternal behaviours
However, it also has powerful immunomodulatory effects and might influence the development of autoimmune disorders that preferential occur in women or during pregancy
What are the biological effect and behavioural outcomes of brain-derived neurotropic factors (BDNF)?
Supports survival or neurons, encourages growth and differentiation of new neurons; and promote synaptic growth/plasticity
It also influences memory processes, stress responses, and mood states; disruption of neurotrophins can be implicated in a variety of psychological disorders
What are the biological effects of the following neurotropins:
Basic fibroblast growth factor (bFGF)
Nerve growth factor (NGF)
bFGF - formation of new blood vessels; protective actions in relation to heart injury essential for maintaining stem cell differentiation
NGF - contributes to cell survival; growth & differentiation of new neurons
Describe the function of macrophages
Monocytes leave the bloodstream and covert to macrophages which is a type of antigen presenting cell
It engulfs microorganisms of a foreign particle and presents in on the MHC-II complex to T cells
Describe what happens when we encounter a foreign particle
Our first life defence is our innate immunity - exposure causes rapid activation of NK cells and macrophages (APCs) will engulf the organisms and present them as an epitope
Our adaptive immunity (T cells and B cells) then uses the MHC complex to determine if the epitope is self or pathogen
- Th1 cells will recognize the antigen and inform T cytotoxic cells to begin multiplying - these pro-inflammatory cells bind to infected cells and make hole and inject enzymes that destroy the cell
- Th2 cells work to modulate the effects of Th1 cells but also signal B cells which release antibodies (immunoglobulins) that marks foreign particles and signals complement factors to destroy them (humoral immunity)
- Treg cells then suppress cytotoxic T cells and prevent immune over activation
- T and B cells (and a lesser extent NK cells) develop memory for pathogen and are thus primed for a sensitized and proliferate immune response if there is a secondary exposure
What are cytokines?
They are immune messaging molecules that are released by immune cells and microglia to communicate with other immune cells
What is the relationship between cortisol and the immune system?
Cortisol is activated by inflammatory stimuli which can in turn dampen the inflammatory immune functioning
What is sterile inflammation?
An immune response that is promoted by non-infectious agents or events
When cells are stressed they release danger-associated molecular patterns (DAMPs) which stimulate pattern recognition receptors (PRRs) which effect immune and inflmmatory processes
PRRs can promote inflammation and encourage progression of disease
What happens to a babies microbiota who is born via caesarean delivery?
Since babies receive bacteria when passing through the vaginal canal sometimes babies who are born via cesarean lack the commensal bacteria making them more susceptible to illness from bacteria found in hospitals
Having a diverse microbiota is crucial for immunity as it increases the ability to fight off a greater variety of bad bacteria
How can people increase the diversity of their microbiota?
- Fecal transplant
- Vaginal Seeding
- Diet
- Probiotics and probiotics might be able to reduce chronic disorders of the gut
What is the difference between processor and systematic stressors?
Processive - involve cognitive processing and may be either psychogenic (psychological) or neurogenic (physical origin)
Systemic - lack of cognitive processing, something we are unaware of
Using primary and secondary appraisals discuss what occurs when someone encounters a potential stressor
Primar appraisal occurs when a person considerers whether the stressor is a risk or not, influenced by social heuristics and personal experiences
Secondary appraisals is when a person considers if they have the coping resources necessary to meet the demands of the stressor, influenced by social influences
If the person does not feel equip to deal with the stressor a stress response involving neurobiological, emotional, and behavioural coping responses will ensue, effects which can be dampened with a social buffer
Using priming and anchoring discuss how people make decisions
In a moment of immediate decision making we are primed to make decisions in a particular way based heuristics established from previous experiences - not always appropriate and can be impacted by your current mood (system 1 - fast thinking)
When making decisions about things wi lack information about we look for anchors - things we know that can help guide our behaviour
Discuss the following characteristics of stressors:
Controllability Unpredictability Uncertainty Ambiguity Complexity Volatility
Controllability - uncontrollable stressors can favour development of the cognitive schema of helplessness which influences motivation/ability to handle future stress
Unpredictability - knowing the event will happen but unsure of when/severity/specific characteristics can make a stressor more aversive
Uncertainty - don’t know if the event will happen (can also be unpredible) will increase aversiveness due to lack of preparation allowed
Ambiguity - when the risk/info is unclear there is an increase in neuronal activity and people often adopt a representative heuristic in which they appraise the situation based on similar experience
Complexity - if a situation is too complex a person may resort to simplified coping/problem solving as it is too difficulty to work out all the possible responses
Volatility - stressors that change very quickly and may require us to adapt and change our coping strategies
What is stress sensitization?
Stressful experiences can impact how we respond to future stressors by priming or sensitizing our biological systems and influencing how we appraise situations having a more dramatic response to subsequent stressors
Describe allostatic and allostatic overload
When an individual encounters an acute stressor there are biological changes to deal with that stressor such as an increase in synthesis and thus production of NTs to maintain a balance, known as allostatisis
When a stressor is severe or experienced for a prolonged time the biological systems cannot keep up and can become overly taxed, known as allostatic overload, increasing sucesebility to negative consequences and illness
Describe stress proliferation
When someone is experiencing significant stress it can give rise to more stressors in their life due to behaviour change, lack of resources, lack of social support, etc.
If someone is ill they may not be able to work which decreases their financial stability, influences their patenting abilities as they don’t feel well, causes a change in behaviour which may push their social support circle away, etc.