The human outer ear (auricle, external auditory canal) and middle ear (ossicles, auditory chain) transmit sound signals to the inner ear, where a structure called the cochlea is responsible for auditory perception. At the same time, the brain sends regulatory signals to regulate sound perception. A lesion in any one of the auditory pathways can lead to deafness. Deafness resulting from lesions in the outer and middle ears is called conductive deafness; deafness resulting from lesions in the cochlea, auditory nerve and auditory center is called sensorineural deafness; deafness resulting from lesions in both is called mixed deafness.