ERP measure of attitudes
a physiological measure of attitudes based on electrocortical activity. The procedure makes use of the phenomenon that one component of event-related potentials (ERPs), the late positive potential (or P300), varies as a function of categorization of stimuli. This component is large when a target stimulus is judged to be inconsistent with the context in which it is encountered and small when it is judged to be consistent with the context. To assess attitudes, the target attitude object is evaluated as part of a series of objects that are either positive or negative in nature. If a large late positive potential is produced when the attitude object is evaluated in the negative context and a small positive potential is produced when it is evaluated in the positive context, this indicates a positive attitude. The reverse pattern indicates a negative attitude. [originally developed by U.S. psychologists John T. Cacioppo (1951– ),
Stephen L. Crites Jr. (1967– ), and their associates]