[Ultrastructure of the central nucleus of the inferior colliculus of the cat midbrain].

Ultrastructure of the central nucleus in the cat posterior colliculus was studied (cells, fibres, synaptic architectonics). Three types of amyelinated fibres were determined: with great number of mitochondria, with usual number of mitochondria, with large amount of granulated vesicles. The results obtained were compared with the data of electron microscopic study of the inferior geniculate body, as they are subcortical formations belonging to the same auditory system but differentiating in their functions. Possible physiological interpretations of the results are considered.