Some sources of variance in skin conductance.

An attempt was made to identity some of the factors that might contribute to the variance associated with skin conductance. Results confirmed earlier findings that Blacks have lower levels of skin conductance than Caucasians. The precise role of skin albedo is difficult to determine because within these groups there appears to be a negative relationship between skin reflectance and skin conductance. Possibly peripheral blood flow differences are responsible. There were no differences in heart rate or in self-report measures of arousal between the groups, and the contribution of personality variables to skin conductance variance was, in part, anomalous.