Effects of chronic cochlear de-efferentation on auditory-nerve response

The olivocochlear bundle was sectioned at the floor of the fourth ventricle in a series of cats. From three to thirty weeks post-operatively, recordings were made from single auditory-nerve fibers. Tuning curves, spontaneous discharge rates, and rate-level functions for tones at the characteristic frequency were measured and compared to normal data. Light- and electron-microscopic analysis of the cochleas suggested the lesions were complete, for both classes of cochlear efferents, in three cases. Electrophysiological data from these cases showed normal thresholds, tuning curves and rate-level functions; however, the distributions of spontaneous activity suggested significant decreases in average rates in the de-efferented cases.

[1]  P. Emson,et al.  Localization of calcitonin gene-related peptide in the organ of Corti of the rat: an immunohistochemical study , 1985, Brain Research.

[2]  R. Kimura,et al.  Termination of the olivo-cochlear bundle in relation to the outer hair cells of the organ of Corti in guinea pig. , 1962, Acta oto-laryngologica.

[3]  Churchill Ja,et al.  The relationship of acetylcholinesterase in the cochlea to the olivocochlear bundle. , 1959, Henry Ford Hospital medical bulletin.

[4]  M. Liberman Single-neuron labeling in the cat auditory nerve. , 1982, Science.

[5]  W T Magruder SECTION D--MECHANICAL SCIENCE AND ENGINEERING. , 1904, Science.

[6]  R. Altschuler,et al.  Enkephalin-like immunoreactivity of olivocochlear nerve fibers in cochlea of guinea pig and cat. , 1981, Proceedings of the National Academy of Sciences of the United States of America.

[7]  Brown Mc,et al.  Morphology of labeled efferent fibers in the guinea pig cochlea , 1987, The Journal of comparative neurology.

[8]  R. Barlow,et al.  Light and efferent activity control rhabdom turnover in Limulus photoreceptors. , 1979, Science.

[9]  Denervation study of synapses of organ of corti of old world monkeys , 1980, The Journal of comparative neurology.

[10]  M. Charles Liberman,et al.  Rapid assessment of sound-evoked olivocochlear feedback: Suppression of compound action potentials by contralateral sound , 1989, Hearing Research.

[11]  O. Densert Adrenergic innervation in the rabbit cochlea. , 1974, Acta oto-laryngologica.

[12]  M. Charles Liberman,et al.  Effects of contralateral sound on auditory-nerve responses. I. Contributions of cochlear efferents , 1989, Hearing Research.

[13]  C. Smith Innervation pattern of the cochlea. The internal hair cell. , 1961, Transactions of the American Otological Society.

[14]  M. Liberman,et al.  Efferent synapses in the inner hair cell area of the cat cochlea: An electron microscopic study of serial sections , 1980, Hearing Research.

[15]  M. C. Brown,et al.  Physiology and anatomy of single olivocochlear neurons in the cat , 1986, Hearing Research.

[16]  J. Guinan,et al.  Differential olivocochlear projections from lateral versus medial zones of the superior olivary complex , 1983, The Journal of comparative neurology.

[17]  Donald Robertson,et al.  Horseradish peroxidase injection of physiologically characterized afferent and efferent neurones in the guinea pig spiral ganglion , 1984, Hearing Research.

[18]  M. Liberman,et al.  Hair cell condition and auditory nerve response in normal and noise-damaged cochleas. , 1979, Acta oto-laryngologica.

[19]  B. M. Johnstone,et al.  Temporary threshold shift modified by binaural acoustic stimulation , 1982, Hearing Research.

[20]  Pierre Bonfils,et al.  Efferent tracts and cochlear frequency selectivity , 1986, Hearing Research.

[21]  M. Liberman,et al.  Afferent and efferent innervation of the cat cochlea: Quantitative analysis with light and electron microscopy , 1990, The Journal of comparative neurology.

[22]  J. Mills,et al.  Cochlear Potentials and Electron Microscopy Applied to the Study of Small Cochlear Lesions , 1973, The Annals of otology, rhinology, and laryngology.

[23]  Brown Mc,et al.  Morphology of labeled afferent fibers in the guinea pig cochlea , 1987, The Journal of comparative neurology.

[24]  J. Guinan,et al.  Effects of electrical stimulation of medial olivocochlear neurons on ipsilateral and contralateral cochlear responses , 1987, Hearing Research.

[25]  M. Liberman,et al.  Auditory-nerve response from cats raised in a low-noise chamber. , 1978, The Journal of the Acoustical Society of America.

[26]  R. Pujol,et al.  Effects of section of the medial efferent tracts (crossed and uncrossed) on cochlear frequency selectivity , 1986, Hearing Research.

[27]  A. Nuttall,et al.  The temperature dependency of neural and hair cell responses evoked by high frequencies. , 1983, The Journal of the Acoustical Society of America.

[28]  John J. Guinan,et al.  Efferent innervation of the organ of corti: two separate systems , 1979, Brain Research.

[29]  M. Liberman The cochlear frequency map for the cat: labeling auditory-nerve fibers of known characteristic frequency. , 1982, The Journal of the Acoustical Society of America.

[30]  John J. Guinan,et al.  Effects of electrical stimulation of efferent olivocochlear neurons on cat auditory-nerve fibers. II. Spontaneous rate , 1988, Hearing Research.

[31]  N. Kiang,et al.  Effects of electric stimulation of the crossed olivocochlear bundle on single auditory-nerve fibers in the cat. , 1970, The Journal of the Acoustical Society of America.

[32]  W. Buño,et al.  Auditory nerve fiber activity influenced by contralateral ear sound stimulation , 1978, Experimental Neurology.

[33]  K. Osen,et al.  Histochemical localization of cholinesterases in the cochlear nuclei of the cat, with notes on the origin of acetylcholinesterase-positive afferents and the superior olive. , 1969, Brain research.