Control of Diastolic Blood Pressure in Man by Feedback and Reinforcement

When provided with external feedback of their diastolic blood pressure and incentives to respond appropriately, normal male Ss learned to raise or lower their diastolic pressure in a 35-min training session. The difference between increase and decrease groups at the end of conditioning was 7.0 mm Hg or 10% of baseline. This difference was augmented to 10.4 mm Hg or 15% of baseline during extinction when half the Ss were asked to maintain continuing “voluntary control” even though feedback and incentives were withdrawn. Heart rate was also influenced when diastolic blood pressure was reinforced, although less markedly. Further analysis indicated that when diastolic pressure is reinforced, heart rate is partially reinforced in the same direction, accounting for the coincidental conditioning of the related cardiovascular measure. No consistent changes in respiration or post-session verbal reports were obtained. These results lend support to the possibility of therapeutic application of the techniques in patients with essential hypertension.