The physiological measurement of acute stress (public speaking) in bank employees

An evaluation of a number of non-invasive physiological measures of stress was conducted, using bank employees attending a two-week residential course. The stressor involved was the preparation and delivery of a 15-min public lecture. The physiological parameters measured were urinary excretion rates of noradrenaline (NA), adrenaline (A), dopamine and cortisol, the ratio of NA/A, salivary cortisol levels, heart rate and blood pressure. Measurements were taken at 08.30, 10.30, 12.30, 15.30 and 17.30 h on the day of the public lecture and on the following (control) day. The public lectures were given between 10.30 and 12.30 h. The urinary excretion rates of adrenaline and cortisol were significantly elevated immediately following, but not before, the public lectures. The ratio NA/A was significantly decreased and the salivary cortisol levels were significantly increased both immediately before and after the public lecture. Urinary excretion rates of noradrenaline and dopamine, blood pressure and heart rate were unchanged by the stressor. Measurement of salivary cortisol levels, as well as providing a simple, stress free, non-invasive collection procedure, more closely reflects in time the changes in plasma levels of the hormone, not suffering from the large lag-time involved with urinary hormone measurements. Salivary cortisol measurement would appear to be the measurement of choice in human stress studies where individual stress factors are to be identified and studied. The significance of the stress-induced elevation in cortisol and catecholamine levels in the link between illness and occupational stress is discussed.