Old age and Health Flashcards
What does the HPA axis stand for?
Hypothalamus-Pituiatry-Adrenal axis
What does the SAM system stand for?
Sympathomedullary system
What happens when an acute stressor is experienced?
The amygdala perceives a situation as a threat
It send a signal to the hypothalamus
The hypothalamus activates the sympathetic nervous system
The sympathetic nervous system sends a signal to the adrenal medulla to release adrenaline and nonadrenaline
This is responsible for the “fight or flight” response, e.g. more energy, faster heartbeat, alertness. The response excess glucocorticoids also mean that the immune system is working harder which can protect us if we are attacked
When happens in terms of chronic stressors?
Chronic stressors are everyday stressors that are experienced over a prolonged period of time
The HPA axis regulates the stress response and in terms of acute stressors can do this effectively
The process in which this happens is that the hypothalamus activates corticotrophin release factors (CRFs) to act on the pituatry gland. The pituatry gland then releases adrenocorticotrophic hormones (ACTH) to stimulate the adrenal cortex to release cortisol.
However, if the HPA axis is continously activated this can have adverse effects, as glucorticoids are continously released which bind to glucocorticoid receptors and prohibit their inflamattory effects.
Explain the vaccination paradigm and what is it used for
The vaccination paraidgm has become popular in ‘in vivo’ - study within the living - psychoneuroimmunology.
The typical protocol is that a baseline measure of antibodies is taken from a healthy individual
The individual is then purposefully exposed to a weakened version of a virus, e.g. influenza virus
Further blood samples are taken as follow-ups to measure the antibody titre
The poorer the antibody titre, the less effective their immune response is
What is psychoneuroimmunology?
The study of the effect of the mind on health and resistance to disease
Explain the vaccination study that looked at chronic stress in elderly care givers
Vedhara (1999)
- 50 spousal care givers (dementia)
- vs. control group (similar SES)
- Measure of anxiety and depression
- Measure of stress
- Salivary cortisol - 3x a day
- Influenza vaccine
- Antibody titres to each strain measured every week
- Elderly carers of spouses with dementia had increased activation in the HPA axis, and a poorer antibody response
Explain the study that showed the link between stress and the common cold
Cohen (1991)
- aprox 400 healthy subjects
- Questionnaire assessing degrees of psychological stress
- Nasal drops: 1 of 5 respiratory diseases vs. saline drops
- Quarantined and monitored
- Respiratroy infection and clinical colds increase with degree of psychological stress
Explain the later study that showed what mediates the link between stress and the common cold
Cohen (2006)
- Positive emotional style (PES)
- Mediates the link between susceptibility to illness and stress
Explain the relationship between old age and happiness
Stone (2010)
- U-bend of wellbeing
- Self-reported wellbeing improves beyond middleage
- People get happier as they get older
What was the critical appaisal to Stone (2010)’s U-bend of wellbeing?
Lachman (2015)
- Only for certain coherts (e.g. baby bloomers)
- Only in terms of life satisfaction
- Sense of control is important to happiness
What other links have been found between aging and the biological systems?
Lutgendorf and Costanzo (2003)
- Immune and neuroendocrine changes
- Reduction in HPA axis responsitivity to acute stress
- Slower stress recovery
- Psychosocial correlated of immune and endrocrine functioning: stress of care giving
