Scheme of neurones of auditory pathway. 4 neuronal afferent centripetal tract terminating in the primary acoustic cortex of temporal lobe. Receptor: hairs cells of Corti organ inside the membranous cochlear duct of inner ear. Receptors are surrounded by dendrites of bipolar neurons of the cochlear ganglion (1. N). Axons of bipolar neurons form the cochlear nerve. Cochlear nerve terminates in the cochlear nuclei (2. N) in the brainstem. From cochlear nuclei information go by the lateral lemniscus into the inferior collicle (3. N) in the mesencephalon. Signals interpolate in the inferior collicle and continue to the medial geniculate body (4. N). The last part of the auditory tract – acustic radiation (geniculo-cortical tract) continue into the upper part of the temporal lobe – transverse temporal gyruses (primary acustic cortex). Between the basic neurons of the auditory pathway there are inserted interstitial (relay neurons) which are grouped into independent nuclei : nucleus olivaris superior, nucleus corporis trapezoidei, nucleus lemnisci lateralis.