Single fiber mapping of spatial excitation patterns in the electrically stimulated auditory nerve

• Published in: Hearing research Vol. 29; no. 2; pp. 195 - 206
• Main Authors: van den Honert, C., Stypulkowski, P.H.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 1987; Elsevier
• Subjects: Acoustic Stimulation; Animals; Auditory nerve; Auditory Threshold; Biological and medical sciences; Cats; Cochlear implant; Cochlear Nerve - physiology; Diseases of the ear; Electric Stimulation; Electrical stimulation; Electrodes; Ent and stomatology; Evoked Potentials, Auditory; Medical sciences; Multiple electrode; Nerve Fibers - physiology; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Single fiber; Spatial selectivity; Vestibulocochlear Nerve - cytology; Vestibulocochlear Nerve - physiology; Electrical stimulation; Cochlear implant; Auditory nerve; Spatial selectivity; Multiple electrode; Single fiber; Cartography; Cochlea; Electric; Instrumentation therapy; ENT disease; Stimulation; Excitation; Experimental study; Nerve fiber; Hearing loss
• ISSN: 0378-5955; 1878-5891
• DOI: 10.1016/0378-5955(87)90167-5

Spatial maps of electrical excitation were constructed by comparing electrical threshold with acoustic CF for large populations of auditory nerve fibers in cats. Thresholds among fibers with the same CF varied by factors of 4 or more. Monopolar electrodes, both intracochlear and extracochlear, excited fibers throughout the cochlea without spatial selectivity. Stimulation with intracochlear bipolar electrodes produced a minimum in the threshold distribution adjacent to the electrodes. With longitudinally oriented pairs, the width, depth, and location of the minimum shifted with stimulus polarity; spread of excitation throughout the cochlea occurred with stimulus intensities 6.2 to 14 dB above the lowest threshold. With radially oriented pairs, minima were sharper and deeper; spread of excitation occurred at intensities 23.7 to 32.8 dB above the minimum threshold.