Electrodermal activity in patients with unilateral brain damage

Electrodermal activity has been studied in patients with focal brain injury mainly to evaluate hypotheses about the relative contribution of the two cerebral hemispheres to emotional processes. Theoretical proposals on this issue originated from the clinical observations indicating different emotional reactions following damage in either hemisphere. Left brain damaged (LBD) patients display what has been defined as a “catastrophic reaction”: failures in neuropsychological testing may induce crying, swearing, or declaring their impotence (Gainotti, 1969, 1972). Often this reaction has an abrupt onset and offset. Reactions of right brain damaged (RBD) patients are in sharp contrast with this pattern; often these patients appear unconcerned with their symptoms (e.g., arm paralysis) which are treated in a matter of fact fashion (indifferent reaction) 1. At times, patients may even appear fatuous and lacking in inhibition (Gainotti, 1972). Somewhat similar reactions have been reported in the case of transient inactivation due to amytal sodium injection (e.g., Terzian and Cecotto, 1959).