Inhibitory interactions in neuronal networks including cells of the auditory cortex and the medial geniculate body

The use of the method of cross-correlation analysis has made it possible to identify some specific features of inhibition in neuronal networks including cells from various loci of the auditory cortex (AC) and the medial geniculate body (MGB). It was demonstrated that inhibitory MGB (AC) neurons possess "convergent" properties which are manifested in the fact one neuron simultaneously excites cells located in various loci of the AC and MGB, and "divergent" properties which are manifested in the fact that one and the same neuron may simultaneously inhibit neighboring cells and neurons from one or several AC (MGB) loci. There are short-axon inhibitory neurons in the AC which selectively act on the activity of one neighboring cell. An inhibitory AC neuron may be simultaneously included in the circuit of afferent and backward inhibition. Reciprocal connections between inhibitory MGB neurons were found. Simultaneous afferent inhibition of remote AC cells may lead to synchronization of their activity. The results make it possible to explain deviations from the principle of tonotopic organization in the AC and MGB.