Abstract
A wide variety of behavioral and physiological data were presented which were discrepant and unrelated without the use of two integrating hypotheses. The behavioral hypothesis was generalized from the distinction of passive and active avoidance by making passive avoidance a subset of the class “inhibit-attentive-responses,” while the physiological hypothesis was generalized from both anatomical and physiological data to show that the inhibit-attentive and passive-avoidance classes of phenomena have an extensive physiological substrate similar to the Papez circuit. The precision of control over the initiation and maintenance of attentive behaviors was hypothesized to be a function of these inhibitory capacities. The hypotheses were discussed in relation to the literature in order to demonstrate their use.