The Neural Substrates of Cognitive Event-Related Potentials: A Review of Animal Models of P3

Abstract

One reaso.n to study the electrical activity of the brain is that the knowledge game.d might be useful for understanding the neural basis of cognitive functions. In other words, endogenous or cognitive event-related potentials (ERPs), which are averaged field potentials that are sensitive to manipulations of psychological variables, could provide evidence to constrain theories on the brain mechanisms that mediate cognition. The success of this approach, however, depends on the extent to which two types of relationships can be substantiated: relationships between ERPs and theories of cognition and relationshlps between ERPs and particular neural events, structures, or systems. Although cognitive ERPs have been thoroughly characterized only in humans, critical evidence for clarifying the neurophysiological substrates of cognitive ERPs may come from studies in animals (Galambos and Hillyard, 1981). This review focuses on recent studies that have begun to develop ammal models of a particularly well-characterized cognitive ERP, the P3 or P300 potential. To develop criteria for assessing these ammal models, the characteristics of P3 in humans are first outlined. Evidence pertaining to the adequacy of each of the putative animal models is then discussed by species, along with evidence about the neural basis of th:se ERPs. The concluding section will reflect on prospects for understandmg the neural basis of P3 and on the usefulness of the animal approach.