Abstract: | ![]() Forty subjects, given binary and proportional auditory and visual feedback and asked to raise and lower their heart rate on signal, were able to produce increases of up to 46 bpm and decreases of up to 14 bpm, with a mean increase over 5 experimental days of 11 bpm and a decrease of 5 bpm. Increases in both diastolic and systolic blood pressure and increases in skin potential level and number of skin potential responses accompanied voluntary increases in heart rate but not decreases. Subjects with the highest resting heart rate variability and skin potential level were best able to raise their heart rate. Subjects with the highest resting heart rate and highest resting heart rate variability were best able to decrease the heart rate. Subjects with high Ego Strength scores (or low Welsh's Factor A scores) on the MMPI were best able to control their heart rate. The Ego Strength score, resting heart rate, and resting heart rate variability were all significantly intercorrelated. Subjects showed marked individual differences in ability to control heart rate, although there was a significant correlation between ability to raise and ability to lower heart rate. |