Effect of vasoconstriction on galvanic skin response amplitude

Abstract

Vascular mediation of the effect of cooling on galvanic skin response (GSR) amplitude was investigated by maintaining a finger site under isothermal conditions while inducing reflex vasoconstriction by cooling the rest of the hand in a water bath at 15 C. This procedure caused an initial increase in GSR amplitude, relative to that on the opposite (control) hand, followed by a steady decline to levels significantly lower than normal. Base resistance was generally unaffected. Smaller GSR waves frequently showed a paradoxical increase in size at the same time as larger ones were attenuated. In control runs in which the insulated chamber acted as a calorimeter the fall of temperature occasioned by arterial occlusion of the finger was of the same order as that produced by cooling. Arterial occlusion accompanying cooling did not change the temperature drop and it was concluded that a cooled blood supply could not account for the observed effects. Rather they appear to depend on cutaneous vasoconstriction. This conclusion implies an artificial relation between vasomotion and GSR as autonomic measures whenever pronounced vasoconstriction occurs. effect of vasoconstriction on skin resistance; temperature effect on skin resistance; temperature effect on GSR; effect of blood supply on electrodermal measures; reflectance plethysmography Submitted on July 22, 1963