3.2 Measuring stress - School

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Psychology
3.2 Measuring stress
Psychology
Learning outcomes
Understand these three studies related to measuring
stress:
• Physiological measures (Geer, J. and Maisel, E.
(1972) ‘Evaluating the effects of the predictioncontrol confound’, Journal of Personality and Social
Psychology 23 (3), 314–19);
• Self-report (Holmes, T. H. and Rahe, R. H. (1967)
‘The social readjustment rating scale’, Journal of
Psychosomatic Research 11, 13–18);
• Combined approach (Johansson et al. (1978) ‘Social
psychological and neuroendocrine stress reactions
in highly mechanised work’, Ergonomics 21 (8),
583–99).
Psychology
Physiological measures
Key study: Geer and Maisel (1972)
Aim
• To see if perceived control or actual control
can reduce stress reactions to aversive
stimuli (photos of crash victims).
Method
• Laboratory experiment.
Psychology
Participants
• 60 psychology undergraduates from New York
University.
Design
• Independent design as participants were
randomly assigned to one of three conditions.
Psychology
Procedure
• Each participant was seated in a sound-shielded
room and wired up to galvanic skin response (GSR)
and heart-rate monitors.
• Group 1 were given actual control over how long
they saw each photograph for.
• Group 2 were yoked to the actual control group,
warned how long the photos would be shown for
and that a noise would precede them.
• Group 3 were also yoked to actual control group,
but were told that that from time to time they
would see photographs and hear tones.
Psychology
Procedure (cont.)
• A Beckman Model RB polygraph was used to
collect psycho-physiological data.
• The data was converted from a voltmeter to a
printout.
• Each recording was performed in a sound and
electrically-shielded room to ensure no audio or
visual input from the projector would interfere
with the data collection.
Psychology
Procedure (cont. 2)
• The heart monitors were attached in standard
positions, and the GSR electrodes were placed
between the palm and forearm of the
participants’ non-preferred arm e.g. left arm
for right-handed people.
Psychology
Findings
• The predictability group (Group 2) were most
stressed by the tone as they knew what was
coming, but did not have control over the
photograph.
• The control group (Group 1) were less stressed
by the photograph than the predictability group
and no-control group (Groups 1 and 2) as they
had control.
Psychology
Conclusions
• It is likely that having the control to terminate
aversive stimuli reduces the stressful impact of
those stimuli.
Psychology
Self report
Key study: Holmes and Rahe (1967)
Aim
• Creating a method that estimates the extent to
which life events are stressors.
Psychology
Method
• A questionnaire designed to ascertain how
much each life event was considered a stressor.
Participants
• 394 subjects.
Psychology
Procedure
• Each participant was asked to rate a series of
43 life events.
• Marriage was given an arbitrary rating of 500
and each event was to be judged as requiring
more or less readjustment.
• It could be based on personal experience and
perceptions of other people.
• The final Social Readjustment Rating Scale was
completed based on the mean scores.
Psychology
Findings
• Correlations between groups were tested and
found to be high in all but one group.
• Males and females agreed.
• Participants of different ages, religions,
educational level agreed.
• There was less correlation between white
and black participants.
Psychology
Conclusions
• The degree of similarity between different
groups is impressive and shows agreement in
general about what constitutes life events and
how much they cause stress (or readjustment).
Psychology
Combined approach
Key study: Johansson et al. (1978)
Aim
• To measure the psychological and physiological
stress response in two categories of employees.
Method
• A quasi-experiment where workers were
defined as being at high risk (of stress) or in a
control group.
Psychology
Participants
• 24 workers at a Swedish sawmill.
•The high-risk group was 14 workers who
had to work at a set pace. Their job was
complex and they were responsible for
their own and their team’s wages.
•The control group was 10 workers who
were cleaners, or maintenance men.
Psychology
Design
• An independent design with participants
already working in one of the two categories,
so no manipulation of the independent
variable.
Psychology
Procedure
• Each participant was asked to give a daily urine
sample when they arrived at work and at four
other times during the day. They also gave selfreports of mood and alertness plus caffeine and
nicotine consumption.
• The baseline measurements were taken at the
same time on a day when the workers were at
home.
Psychology
Procedure (cont.)
• Each participant gave a urine sample four times
during the day, so that their adrenaline levels
could be measured. Their body temperature
was also measured at the same time. These
physiological measurements gave an indication
of how alert the participants were.
• Self-rating scales of words such as ‘sleepiness’,
‘wellbeing’, ‘irritation’ and ‘efficiency’ were
made on scales from none to maximal (the
highest level the person had ever experienced).
• Caffeine and nicotine consumption were noted.
Psychology
Findings
• The high-risk group had adrenaline levels twice
as high as their baseline and these continued to
increase throughout the day. The control group
had a peak level of 1 ½ times baseline level in
the morning and this then declined during the
rest of their shift.
• In the self-report, the high-risk group felt more
rushed and irritated than the control group.
They also rated their wellbeing lower than the
control group.
Psychology
Conclusions
• The repetitive, machine-paced work, which was
demanding in attention to detail and was highly
mechanised, contributed to the higher stress
levels in the high-risk group.
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