[Interaction of reactions induced by acoustic and somatosensory stimuli in neurons of the magnocellular portion of the medial geniculate body].

Interaction between impulse activities evoked by a click and contralateral forepaw electrical stimulation was studied in 78 neurons of magnocellular part of the medial geniculate body in cats immobilized with myorelaxine. Among the studied neurons 33 responded by impulse activity both to a click and forepaw stimulation, 25--exclusively to a click and 20--only to stimulation of the forepaw or spinal cord dorsal funiculus. Conditioning stimulation produced inhibition of impulse responses to test stimulus in 32 neurons and only in one neuron facilitation was observed. The inhibition of neuronal activity evoked by a click was longer than that produced by forepaw stimulation. Responses to a click were inhibited by forepaw stimulation in all studied neurons but the responses evoked by forepaw stimulation were inhibited by a click only in four out of 20 neurons. A conclusion is made that inhibition of impluse activity in neurons of the magnocellular part of the medial geniculate body during interaction of volleys evoked by a click and forepaw stimulation is postsynaptic in its nature.