[THE INFLUENCE OF LOCUS COERULEUS ON DIFFERENT ACTIVITIES OF THE THALAMO-CORTICAL SYSTEMS]

As revealed from our experiments, in facilitation of passage of the thalamo-cortical visual signals a key role is attributed to variability of activity of visual neurons in reticular nucleus of the thalamus. It was demonstrated that a facilitatory action of locus coeruleus gets augmented following functional exclusion of the thalamic reticular nucleus. Nevertheless, stimulation of locus coeruleus stipulated facilitation of neuronal activity in the anterior part of thalamic reticular nucleus. Emerging from this data one may assume that in the inhibition of evoked responses from a sensorimotor area of the neocortex in response to stimulation of locus coeruleus a certain role is played by reticular nucleus of the thalamus. Namely, augmentation of neurons activity in the anterior part of the thalamic reticular nucleus must condition inhibition of neuronal activity in the ventral nuclei. In spite of the stated, it is not excluded locus coeruleus ha-ving an immediate, direct inhibitory action on the neuron activity within the sensorimotor cortex and thalamic ventral nucleus.