Characteristics of palmar skin potential and conductance in relaxed human subjects.

Abstract

ABSTRACTAn investigation of mechanisms generating palmar skin potential level (SPL) was undertaken from relaxed subjects in a non‐arousing environment. In these circumstances it was possible to obtain recordings where there were no skin potential responses (SPRs). At such times of quiescence, SPLs, recorded with 0.5% KCl as the external electrolyte medium, had characteristics which differed from SPLs recorded when there were SPRs. The potentials recorded at the beginning of these periods of quiescence were designated “basal” skin potential levels (BSPLs).BSPLs were demonstrated in other than optimal conditions for achieving basal state, i.e., with non‐habituated subjects, and with subjects carrying out an undemanding cognitive task; the relevance of these findings to the use of SPL as an index of arousal in unstimulating conditions is discussed.An interpretation of BSPL phenomena is possible in terms of a relationship between electrode electrolyte and individual values of body fluid potassium.