Self-Control of Systolic Blood Pressure with the Constant Cuff-Pressure System

Abstract

In the present study, we attempted to examine the relationship between each of the two factors related to individual differences and the ability to control systolic blood pressure. The first factor is richness of imagery. The second is intensity of autonomic self perception. Sophian Scale of Imagery (SSI) of 11 items, each of which inquiries about the richness of imagery in daily life and Sophian Scale of Internal Perception (SSP) 0L 15 items, each of which deals with the intensity of autonomic self perception in daily life were administered to 17 undergraduate students. The experiment cnsisted of three segments : (1) an initial pre-experiment baseline median blood pressure determination, (2) 5 rest trials, (3) 15 training trials (either increase or decrease). Each subject was studied in two sessions, one day apart, the first session an increase blood pressure condition, the second a decrease condition, or vice versa. The constant-cuff pressure method of measuring systolic blood pressure was used (Tursky et al. 1972). Each trial onsisted of exactly 30 heartbeats. In training trial, the subjects were given tone feedback when the each heartbeat was accompanied by Korotkoff sound. During any one trial, the pressure applied tothe cuff was held constant. If more than 75% of thehear tbeat-Korotkoff sound contingencies were successful on the trial, the applied pressure was increased by 2-3mmHg on the next trial. In the case of success on fewer than 25%, the task was made easier by 2-3 mmHg. An adjustment was not made at 75% to 25%. The results for systolic blood pressure control are shown in Fig. 2. An analysis of variance of direction (Up vs Down) and trials were not significant. A t-test between Up and Down were significant in 12,14 and 15 trial (p<.05). Table 1 shows the relationship between the scores of each scale and the ability to control systolic blood pressure. This suggests a tendency for the increase and decrease blood pressure conditions to have differential effects.