Emotional Behavior Produced by Hypothalamic Stimulation

Abstract

In unanesthetized, unrestrained cats, the hypothalamus was stimulated with implanted electrodes. Responses depended on electrode position, and were classified as flight or aggressive reactions. Aggressive responses were, in general, elicited from middle hypothalamic stimulus sites, whereas flight reactions were more commonly elicited from rostral hypothalamic or preoptic sites. Both flight and attack were well-directed and purposeful. In some animals, conditioned responses to a buzzer were established with hypothalamic stimulation as the US. Hypothalamic stimulation was also successfully used to establish a conditioned avoidance response (food avoidance, compartment preference test). Stimulation at electrode sites producing flight reactions elicited a response (paddle-pushing) previously established to avoid a painful shock to the feet. The data suggest that hypothalamic stimulation arouses an affective experience closely akin to that produced by natural stimuli. It is felt that the possibility exists of cortical participation in hypothalamic-induced affective behavior.