Auditory Brain Stem Implantation: Surgical insertion of an electronic hearing device (AUDITORY BRAIN STEM IMPLANTS) with electrodes to the cochlea nucleus in the BRAIN STEM rather than to the inner ear as in COCHLEAR IMPLANTATION.Auditory Brain Stem Implants: Multi-channel hearing devices typically used for patients who have tumors on the COCHLEAR NERVE and are unable to benefit from COCHLEAR IMPLANTS after tumor surgery that severs the cochlear nerve. The device electrically stimulates the nerves of cochlea nucleus in the BRAIN STEM rather than the inner ear as in cochlear implants.Brain Stem: The part of the brain that connects the CEREBRAL HEMISPHERES with the SPINAL CORD. It consists of the MESENCEPHALON; PONS; and MEDULLA OBLONGATA.Evoked Potentials, Auditory, Brain Stem: Electrical waves in the CEREBRAL CORTEX generated by BRAIN STEM structures in response to auditory click stimuli. These are found to be abnormal in many patients with CEREBELLOPONTINE ANGLE lesions, MULTIPLE SCLEROSIS, or other DEMYELINATING DISEASES.Cochlear Nerve: The cochlear part of the 8th cranial nerve (VESTIBULOCOCHLEAR NERVE). The cochlear nerve fibers originate from neurons of the SPIRAL GANGLION and project peripherally to cochlear hair cells and centrally to the cochlear nuclei (COCHLEAR NUCLEUS) of the BRAIN STEM. They mediate the sense of hearing.Auditory Pathways: NEURAL PATHWAYS and connections within the CENTRAL NERVOUS SYSTEM, beginning at the hair cells of the ORGAN OF CORTI, continuing along the eighth cranial nerve, and terminating at the AUDITORY CORTEX.