Abstract: | Microinjection of noradrenaline in to the head of the caudate nucleus failed to influence the latent time of the conditioned reaction of avoidance and the muscle tone, but limited the motor activity and considerably increased the value and the latent time of the food-procuring reflex. Serotonin failed to influence the latent time of the conditioned defence reflex and did not alter the motor activity of rats; however, it shortened the latent period of the conditioned motor-food reflex and markedly stimulated the food-procuring reaction. Dopamine inhibited the conditioned food and defence reflex, but markedly stimulated the spontaneous motor activity of rats. The data obtained pointed to differences in the neurochemical mechanisms realizing the conditioned reflex reactions of different biological modality at the level of the caudate nucleus of rats. |