Differential preparatory cardiovascular responses to aversive and appetitive behavioral conditioning

Dogs were required to press a response panel either to avoid shock or obtain food. During a one-hour interval immediatelypreceding performance on the avoidance task, blood pressure increased while heart rate decreased. In contrast, both blood pressure and heart rate increased during the one-hour interval immediatelypreceding performance on the food task. During both the shock-avoidance and food performancesper se, however, elevations in heart rate and blood pressure were observed, though the avoidance task produced less consistent heart rate changes. These effects were observed (1) with different individual dogs on each of the two training procedures, and (2) with the same dogs exposed successively to both aversive and appetitive behavioral conditioning.