Several membrane-like properties of the effector in the galvanic skin response (GSR) have been measured in humans by comparison of activity at a control site with that of a site subjected to changes of external chemical environment or changes in direction or density of imposed current. Comparison of inorganic chlorides shows that small cations, e.g. K+, may reversibly reduce GSR amplitude and R by 40%; larger cations, e.g. Ca++, increase GSR by several hundred per cent, while at the same time reducing basal resistance (R). GSR and R are reduced by acids and alkalies and by detergents. The effector is a poor rectifier, but there is a pronounced effect of polarity of current on the amplitude of the GSR in the case of large cations or anions combined with smaller ions of opposite charge. Current densities beyond 11 μamp/cm2 produce an ‘injury’ effect manifested in GSR and apparent resistance. These results have been interpreted in terms of an active superficial membrane having a relatively low charge.
Submitted on August 3, 1959