Three ways that stress hormones affect immune functioning
Chronic stress hormones
Prolonged Chronic stress will activate the pituitary adrenal pathway and will produce high levels of cortisol, this inhibits the action of the phagocytes (macrophages) and lympocytes (t-cells) and in turn will lead to suppression of all three types of immunity. In addition to this high levels of corticosteroids will shrink the thymus gland, (this gland produces the body's t-cells) therefore the body will not be able to fight antigens as there will be a reduced number of t-cells.
Finally ACTH produces anti-inflammatory hormones which inhibit immune functioning.
Acute stress hormones
Constant repeated short term stress will activate the sympathomeduallry pathway and will produce high levels of adrenaline in the body. High levels of adrenaline inhibit the action of the helper t-cells and will increase the action of suppressor t-cells. This will lead to immunosuppression as the body will not be ale to defend against forgein antigens in the body.
Prolonged Chronic stress will activate the pituitary adrenal pathway and will produce high levels of cortisol, this inhibits the action of the phagocytes (macrophages) and lympocytes (t-cells) and in turn will lead to suppression of all three types of immunity. In addition to this high levels of corticosteroids will shrink the thymus gland, (this gland produces the body's t-cells) therefore the body will not be able to fight antigens as there will be a reduced number of t-cells.
Finally ACTH produces anti-inflammatory hormones which inhibit immune functioning.
Acute stress hormones
Constant repeated short term stress will activate the sympathomeduallry pathway and will produce high levels of adrenaline in the body. High levels of adrenaline inhibit the action of the helper t-cells and will increase the action of suppressor t-cells. This will lead to immunosuppression as the body will not be ale to defend against forgein antigens in the body.
Direct and Indirect effects of stress
Direct effects of stress on the body can lead to health problems such as: Immunosupression leading to illness and disease,Increased heart rate and blood pressure leading to atherosclerosis, heart disease and strokes.
Indirect effects of stress are any behaviour that occurs because of stress and effects your health.eg. Smoking, Drinking alcohol, Neglecting diet and Drug abuse.
Direct effects of stress on the body can lead to health problems such as: Immunosupression leading to illness and disease,Increased heart rate and blood pressure leading to atherosclerosis, heart disease and strokes.
Indirect effects of stress are any behaviour that occurs because of stress and effects your health.eg. Smoking, Drinking alcohol, Neglecting diet and Drug abuse.
A01. Key study: Cohen et al (1993)
Aim: To investigate the role of general life stress on the immune system.
Procedure:
Procedure:
- 394 healthy participants were first asked to individually complete a questionnaire assessing their number of life events in the last year and rating of stress and negative emotions (eg. depression). These three measures were combined as a STRESS INDEX.
- All participants were exposed to the cold virus and 82% became infected.
- 7 days later participants were asked to return and the number of clinical colds were measured (DV).
A02. Evaluation of the key study
1. One weakness with the study is that it uses self-report techniques as a measure of stress. This is a problem because...
participants may act in a socially desirable way particularly when asked to rate their own stress and negative emotions. This will reduce the internal validity of the questionnaire.
2. The study presents ethical issues as all the participants were exposed to the common cold.
Cohen et al (1993) fails to protect participants from physical harm as they are infected with a virus. However it should be noted that the researchers did ensure that the all the participants were healthy prior to the investigation.
3. One problem with the study is that the findings are correlational therefore…
Cohen et al (1993) cannot infer that stress causes participants to be vulnerable to the common cold but merely that the two variables are associated.
participants may act in a socially desirable way particularly when asked to rate their own stress and negative emotions. This will reduce the internal validity of the questionnaire.
2. The study presents ethical issues as all the participants were exposed to the common cold.
Cohen et al (1993) fails to protect participants from physical harm as they are infected with a virus. However it should be noted that the researchers did ensure that the all the participants were healthy prior to the investigation.
3. One problem with the study is that the findings are correlational therefore…
Cohen et al (1993) cannot infer that stress causes participants to be vulnerable to the common cold but merely that the two variables are associated.