Unexpected adrenergic effects of chlorpromazine: eating elicited by injection into rat hypothalamus

Although chlorpromazine is believed to block adrenergic transmission, injection of this drug into the hypothalamus of satiated rats does not block norepinephrine-elicited eating, but instead mimics norepinephrine by eliciting eating. The amount of eating elicited by norepinephrine and by chlorpromazine is reliably correlated. These results suggest that endogenous norepinephrine mediates eating elicited by centrally injected chlorpromazine.

Instrumental learning of vasomotor responses by rats: learning to respond differentially in the two ears

Curarized and artificially respirated rats were rewarded by electrical stimulation of the brain for changes in the balance of vasomotor activity between the two ears. They learned vasomotor responses in one ear that were independent of those in the other ear, in either forepaw, or in the tail, or of changes in heart rate or temperature. In addition to implications for learning theory and psychosomatic medicine, these results indicate a greater specificity of action in the sympathetic nervous system than is usually attributed to it.

Lateral hypothalamus: learning of food-seeking response motivated by electrical stimulation

Stimulation of the lateral hypothalamus, which induces eating, resembles hunger in that it motivates rats to learn, for food reward, a response of pressing a bar. The response is discriminatively confined to only a bar that delivers food on either a 100-percent or a partial schedule of reinforceinent. This discriminative responding can be transferred to hunger that is normally induced by deprivation of food.

A brief temporal gradient of retrograde amnesia independent of situational change

Rats were given a single electroconvulsive shock at varying intervals after receiving a punishing shock to the feet immediately after stepping into a compartment. Significant amounts of retrograde amnesia for the memory of the punishment was shown when electroconvulsive shock was administered up to and including 30 seconds after the punishment but not at 60 seconds. This brief temporal gradient cannot be explained in ternis of changed stimulus cues or learned interference analogouS to retroactive inhibition.