[System principles in the organization of neurons carrying out cortical inhibition]

Some new data on neuronal and synaptic organization of sensorimotor cortical area in cat are obtained by a complex of morphological and electrophysiological methods. These data permit considering that direct afferent inhibition is ensured by thalamo-cortical neurons and neurons forming the callosal and association links. The recurrent and lateral inhibition are structurally realized through the ascending recurrent axon collaterals of pyramidal neurons forming links either with short-axon or with long-axon interneurons. Cortico-thalamic (cortico-fugal) inhibition may be performed either via descending cortico-thalamic neurons or via cortico-cortical ipsi- and contralateral neurons. The above mentioned neuronal chains may be considered as structural elements of more complex neuronal sets which ensure the inhibition at the cortical inputs, outputs and intracortically.