CARDIAC-RESPIRATORY-SOMATIC RELATIONSHIPS AND FEEDBACK EFFECTS IN A MULTIPLE SESSION HEART-RATE CONTROL EXPERIMENT

An experiment addressing several unresolved issues in operant conditioning of heart rate (HR) in human subjects was performed. Cardiac‐respiratory relationships, cardiac‐somatic relationships, effects of biofeedback, and individual differences were examined in terms of their stability across multiple training sessions. Thirty subjects participated in 3 training sessions. Each session began with 4 trials of attempted HR change without feedback followed by 8 trials with “proportional” feedback of HR. On half the trials HR decrease was attempted while HR increase was attempted on the other half. Subjects were instructed to keep their respiration rate (RR) constant and not to engage in undue movement or muscle activity. Results indicated that subjects were able to produce significant HR increases and decreases from baseline levels, but these changes were accompanied by parallel changes in respiratory and somatic variables which persisted across sessions. Analysis of data from individual subjects was performed to explore the nature of individual differences in cardiac‐respiratory‐somatic patterns. The effects of biofeedback were unimpressive, suggesting at best a minor improvement in cardiac control with increased respiratory concomitance. Cardiac control, feedback effects, and cardiac‐somatic patterns were stable over sessions. There was evidence of some reduction in cardiac‐respiratory parallelism across sessions. Copyright © 1979, Wiley Blackwell. All rights reserved