Laboratory versus naturalistic research

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STRESS
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Physiological measures: Measures were taken of heart rate, skin temperature and
skin conductance level.
Self-report measures: Measures were also taken of the children’s mood (e.g.
Sensation of perceived calmness, subjective feeling of wellness, feeling of perceived
attentiveness) and their physical well-being (e.g. calmness of their heart beats, subjective
body warmth, perceived dampness of the hands).
Results
The results were assessed to examine the impact of relaxation training regardless of type
of relaxation and also to explore whether one form of relaxation training was more
effective.
Physiological changes: The results showed that imagery relaxation was related to a
decrease in heart rate and skin conductance but did not result in changes in skin temperature. In contrast, progressive muscle relaxation resulted in an increase in heart rate
during the training session.
Self report changes: The results showed increased ratings of mood and physical wellbeing during baseline and training sessions for all interventions.
Conclusions
The authors conclude that relaxation training can result in psychophysiological changes
but that these vary according to type of training. What is also interesting, however, is the
degree of variability between the different measures of change. In particular, differences
were found in the changes between different aspects of the children’s physiology – a
change in heart rate did not always correspond to a change in skin temperature. Further,
changes in physiology did not always correspond to changes in self-reported mood or
physical well-being. Therefore a measure indicating that heart rate had gone down did
not always correspond with a self-report that the individual’s heart was more calm.
Laboratory versus naturalistic research
Laboratory research is artificial whereas real life research is uncontrolled. Some studies,
however, illustrate high levels of congruence between physiological responses in the
laboratory and those assessed using ambulatory machines in real life. For example,
Matthews et al. (1986) reported similarity between reactivity following laboratory tasks
and public speaking and Turner and Carroll (1985) reported a correlation between the
response to video games and real life stress identified from diaries. However, other studies
have found no relationship or only some relationship with some measures (e.g. Johnston
et al. 1990). Johnston and colleagues (Anastasiades et al. 1990; Johnston et al. 1990,
1994) designed a series of studies to try to explain this variability. Using a battery of
tasks to elicit stress in the laboratory and ambulatory machines to assess stress reactivity
in real life they concluded that physiological measures taken in the laboratory concord if
the following conditions are met: the field measure is taken continuously; the analysis
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