Concordance among self-regulated responses: is self-regulatory ability a psychophysiological "trait"?

The purposes of this study were to examine whether or not self-regulation of physiological responses demonstrates day-to-day reliability, to determine the degree of individual subject consistency (or concordance) in the ability to self-regulate across several different physiological responses, and, finally, to explore the impact of biofeedback training on interresponse concordance. Twenty normal subjects participated in six bidirectional self-regulation sessions-the first and last sessions involving instructions only, and the remainder, biofeedback. Self-regulation scores consisted of the absolute difference between increase and decrease trial means. The average test-retest reliability coefficients (rs) for the self-regulation scores, across the four biofeedback sessions, were a highly significant .50, .68, .30, and .47 for EEG, EMG, HR, and SCL, respectively. By contrast, the average concordance among the self-regulation scores for the four feedback sessions, estimated by Kendall's coefficient of concordance, was a marginally significant 39% of the possible variance of the rank sums. This corresponds to an average between-response rs value only of .19. The concordance level from the initial no-feedback (i.e., instructions only) session was not significant. Multivariate concordance levels did increase during the first three feedback sessions, but declined at the fourth, and again was nonsignificant during the final no-feedback session. Among the individual self-regulation response pairings, only the EEG/EMG combination was consistently associated during the no-feedback sessions. The present results suggest that self-regulatory ability is neither a highly unitary "trait"-like phenomenon nor an entirely response-specific event, but may vary considerably as a function of subject factors, or the situational circumstances, under which it is measured.