バイオフィードバック指標としての皮膚コンダクタンス変化と皮膚電位活動の比較

抄録

Previous biofeedback studies concerning electrodermal activities have used either skin conductance (SC) or skin potential (SP). This study was designed to investigate the temporal correspondence between SC and SP and to determine the most suitable indicator for electrodermal biofeedback studies. SC and SP were recorded simultaneously in 24 subjects under the mirror drawing test. The following results were obtained : (1) Intrasubject correlation coefficients between total amplitudes per minute of skin conductance response (SCR) and of skin potential response (SPR) were significant in all subjects, whereas correlations between skin conductance level (SCL) and skin potential level (SPL) were significant in only 17 subjects (70.8%). Correlations between SCL and SPL were low or significant negative in subjects showed a positive SPL shift caused by a burst of positive SPRs. (2) Although SCR and SPR, phasic components of EDA, showed a marked increase in total amplitude in the first half of the experiment, but a gradual decreasing of responsiveness was found in the latter half. On the other hand, SCL and SPL, tonic components of EDA, showed consistent responsiveness throughout the experiment. (3) Latency of changes in SPL were significantly longer than changes in SCL. These results suggest that SCL is the most suitable indicator for electrodermal biofeedback studies.