The relationships between drug dosage per injection and response rate, and drug dosage per injection and total daily drug intake were ascertained in Rhesus monkeys which self-administered cocaine, pipradrol, methylphenidate and phenmetrazine intravenously. The study demonstrated the monkeys would selfadminister all of these compounds over a wide range of dosages. Furthermore, the magnitude of reinforcement, i.e., dosage per injection, and the rate of responding in self-administering these compounds were inversely related. However, total daily drug intake was independent of the dosage per injection over a wide range of dosages. The results indicate that either the subjects can compensate for large changes in unit dosage so that daily drug intake remains stable or that a direct effect of these compounds functions in limiting their self-administration.

Hyperemotionality manifested by violent attack or flight reactions in response to previous neutral or innocuous stimuli, has been observed in rats with lesions of the septal area of the brain (hereinafter referred to as "septal rats") (1-4). The hyperemotionality of septal rats was restored to normal by making other lesions in the amygdaloid or administering certain tranquilizing drugs (2, 4-7). From these observations, it was possible to assume that the limbic system exerted an important function in the "physio logical tranquilization" of rats and that tranquilizing drugs might have an effect on this part of the brain.It has recently been reported that rats in which the olfactory bulb had been removed (hereinafter referred to as "O.B.-rats") exerted hyperemotionality similar to that of the septal rats (14, 18), and this hyperemotionality of O.B.-rats was also corrected by making other lesions in the amygdaloid (8).In this report, change in emotional behavior of O.B.-rats was analyzed using the scoring method and the effect of various psychotherapeutic drugs on the hyperemotion ality of these animals was observed. The effects of these drugs are compared with the general activity of normal rats and the taming effect of these drugs is also discussed herein. METHODS 1) Animals and surgical procedureMale albino rats of the Wistar strain each weighing 250-350 g were used. The ani mals were anesthetized with 50 mg/kg of sodium pentobarbital given intraperitoneally and held in a stereotaxic instrument. After a suitable hole bored in the skull with a tre phine, the dura was opened and the olfactory bulb was removed by suction as completely as possible. Sham operation was performed by the same procedure on the same area of the skull. These animals were placed in individual cages with free access to water and food. At the end of the experimental period, the brain of each rat was fixed in 10 per cent formalin solution and sectioned to confirm the correct placement of the lesion.

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