ABSTRACT
T he skin has electric properties that change on the relatively short time scaleof seconds and are closely related to psychological processes. These charac-teristics of skin, known for more than 100 years, have been widely used in research. Changes in electrodermal activity (EDA) and skin conductance are related to changes in eccrine sweating, which are, in turn, related to activity in the sympathetic branch of the autonomic nervous system (ANS). Accordingly, EDA measures have been used to study psychological processes related to sympathetic arousal. For example, skin conductance has become an important tool in studying affective processes because the ANS plays a significant role in emotion and motivation. While increasingly direct methods of assessing neural activity have been developed recently (e.g., fMRI and PET), skin conductance is still often used as a proxy for neural and brain activity because it is relatively cheap and can be measured unobtrusively and reliably.
