Analysis of neuronal processes in activating systems of rat brain during development of the instrumental defense reflex.

We have developed a conditioned defense reflex in chronic experiments with rats using electrodes implanted in the reticular oral pons nucleus, the corticomedial group of amygdalar nuclei, the ventromedial hypothalamic nucleus, and the central gray matter of the midbrain. We showed that the synchronization of the activity of neuronal groups of emotiogenic formations of the brain structures investigated was enhanced during formation of the conditioned reflex. We established a dependence of the correlation of the activity of limbic neuronal groups on the functional state of the reticular formation, and also neurochemical correlation mechanisms. We were able to show that an increase/decrease in the coefficients of mutual correlation of the activity of the neuronal aggregates of limbic structures is accompanied by a change in the parameters of the evoked potentials recorded in them.