Problems in the Use of the Galvanic Skin Response (Gsr) as an Index of Cerebral Function: Implications of the Latent Period¹

When does the GSR indicate cortical, subcortical, spinal, sympathetic, or purely peripheral function? The neural activity initiating the response necessarily precedes it during the latent period. Since the time required for nerve conduction is shown to occupy only a portion of the period from stimulus to detectable response, there is abundant opportunity for central participation. Cortical activity, as shown by familiar EEG a‐blocking, follows almost any attention‐getting or semantic stimulus and typically occurs during the latent period before the appearance of an observable GSR. Rapid diphasic reversal of EEG phase relations suggestive of “intersociative” interplay between cortical areas occurs during the GSR latent period and even precedes blocking, providing further indication of cortical contribution to GSRs resulting from high level associative activity.