Health Psychology, 2nd Edition

26 BIOLOGICAL BASES OF HEALTH AND ILLNESS

behaviour and voice frequency and that a video analysis of the participant’s

performance will also be conducted. The anticipation of giving such a presentation

is the stressor that stimulates the HPA axis. Following receipt of the instructions,

participants return to room A to prepare a speech with the aid of paper and a pen.

After 10 minutes, the participant returns to room B to deliver the speech in front of

the panel. If the speech falls short of 5 minutes, the participant is told ‘You still

have some time left. Please continue’. After 15 minutes, the panel asks the

participant to start to serially subtract the number 13 from 1022 as quickly and

accurately as possible. If an error is made, one of the panel requests that the

participant start again at 1022. After 20 minutes, the task is ended and the

participant returns to room A to rest and be debriefed about the nature of the

experiment and be informed that no voice and video analysis of their performance

will be conducted. The rest period may last between 30 and 70 minutes depending

on which hormones are being monitored.

The TSST has been widely used by health psychologists because it is simple to

administer and researchers can easily monitor changes in a wide range of

cardiovascular (e.g. heart rate, blood pressure) and neuroendocrine (e.g. cortisol,

ACTH) parameters during the paradigm. Changes in salivary and serum (in the

blood) cortisol levels have probably received the most attention in the literature.

A typical cortisol profile (using salivettes) in response to the TSST is shown in

Figure 2.4. Two characteristics of the profile are worth noting: the extent to which

cortisol increases in response to the stressor (i.e. stress reactivity); and the length

of time it takes for cortisol levels to return to baseline (stress recovery). Stress

reactivity and stress recovery are discussed further in Chapter 3.

Cortisol (nmol/l)

16

14

12

10

8

6

4

2

0

–15 0 15 25

Minutes

35 45 55

FIGURE 2.4Typical cortisol profile following the TSST.