gehoorpad

Gehoorpad, or the auditory pathway, denotes the neural route by which sound information travels from the peripheral auditory organs to the cerebral cortex, enabling perception of pitch, loudness and spatial location. It includes the peripheral structures of the ear as well as central auditory pathways in the brain.

Peripheral transduction occurs when sound waves enter the outer ear, are conducted through the middle ear via the tympanic membrane and ossicles, and reach the inner ear. In the cochlea, hair cells transduce mechanical energy into neural impulses carried by the spiral ganglion fibers of the cochlear nerve, a branch of the VIII cranial nerve.

Central pathway entails successive relay stations. From the cochlear nerve, signals project to the cochlear nucleus in the brainstem, then to the superior olivary complex (involved in binaural processing), ascend via the lateral lemniscus to the inferior colliculus in the midbrain, proceed to the medial geniculate body of the thalamus, and finally reach the primary auditory cortex in the transverse temporal gyrus (Heschl’s gyrus) of the temporal lobe. Throughout much of this pathway, tonotopic maps preserve frequency organization, and information from both ears is integrated for localization and complex sound perception.

Functions and clinical relevance include localization, discrimination of frequency and timing, and higher-level processing such as language comprehension. Efferent pathways from cortex to lower auditory centers modulate sensitivity. Disorders can affect any level of the pathway, from conductive or sensorineural hearing loss to central auditory processing disorders; diagnostic tools include auditory brainstem response testing and neuroimaging.