This study examined the combined effects of personality with instruction and treatment variables in human operant heart-rate conditioning. The Edwards Personal Preference Schedule was administered to 50 subjects tested for bidirectional heart-rate control during no-feedback and analogue auditory feedback conditions. Findings indicated that relative to pre-trial baselines, subjects were able significantly to alter heart rates according to instructed direction of change, but treatment effects for augmented sensory feedback were not reliable. Correlational analyses employing personality variables demonstrated that different traits define successful speeding and reduction performance. Further, post hoc analyses for personality high-low classification X treatment X instructions effects indicated that personality variables of succorance and abasement moderated treatment effects for heart-rate reduction. Questions are raised concerning the efficacy of proportional auditory treatment in biofeedback training.