The effects of anticipatory stress on heart rate and T-wave amplitude.

The purpose of the present study was to examine the effects of an anticipatory stressor on three measures of cardiovascular activity: heart rate (HR), T-wave amplitude (TWA) and blood pressure (BP). Twenty-eight males were assigned to either a stress or no-stress group. All subjects reviewed a brief section of prose and then read it aloud during two sessions. The stress group was told that the reading task was a speech and that their performance would be evaluated. The no-stress group was told that the reading task was a part of the readability evaluation of the text material. Reliable increases in HR were observed during both sessions with the stress group exhibiting greater accelerations than the no-stress group. Though TWA and BP varied with periods, no reliable group differences were observed. Degree of threat or aversiveness appears to be indexed more reliably by HR changes than by changes in TWA.