Kiecolt-Glaser et al. (Short term stressors)
P A study done by Kiecolt-Glaser et al. looks at the effect of short term stressors on immunse system functioning in medical students.
E Blood samples were taken one month before (low stress) and during the exam period itself (high stress). They measured NK cell activity in the blood sample tp assess immune system functioning. They found that NK cell activity was signicficantly reduced in the second sample.
C This shows that short term predictable stressors reduce immune system functioning.
AO3: However the study had low population validity as there was only one age group involved i.e. students. This means that we can't generalise the reslts of the study to the whole population.
Marucha et al.
P Another study carried out by Marucha et al. investigates the effect of Exam-related immune changes on the rate at which wounds heal.
E They inflicted a punch bipsy in the mouth of students either 3 days before exams or during the summer holidays.They found that the wounds took 40% longer to heal during the exam period.
C This suggests that short term stressors reduce the rate at which wounds heal.
AO3: This study is reliable as it is biological and cannot be subjective to demand characteristics.
Kiecolt-Glaser et al. (Ongoing Stressors)
P Kiecolt-Glaser et al tested the impact of interpersonal conflict on wound healing.
E They inflicted wounds on the arms of married couples and found that the wounds healed slower after decisions that were conflicting and not supportive.
C This shows that ongoing stressors reduce immune system functioning.
Malarkey et al.
P Malarkey et al. investigated the effects of marital conflict on immune system functioning.
E They studied over 90 newly wed couples over a 24 hour period and asked them to discuss and resolve marital isses likely to produce conflict. They found that marital conflict produced significant changes in adrenaline and noradrenaline.
C This shows that marital conflict can lead to poorer immune system functioning.
AO3: However this study has low mundane realism as at home the conflict would be more negative and last longer and so the effects would be more adverse.