Anatomy of Olivocochlear Neurons

Part of the Springer Handbook of Auditory Research book series (SHAR, volume 38)


Hair cell receptors for the hearing and balance organs, and the lateral line, are unique among the senses by receiving an efferent innervation of the periphery. Olivocochlear (OC) neurons supply this efferent innervation, and they are the most peripheral of the many descending neural systems of the central auditory pathway (see Schofield, Chap. 9). OC neurons are named by their origins in the superior olivary complex and terminations in the cochlea (Fig. 2.1). In the cochlea, they innervate the hair cells and auditory-nerve fibers. This chapter mainly covers the new ground on OC anatomy in mammals since Warr’s (1992) comprehensive chapter on this topic about 15 years ago. Since that time, there is even stronger evidence for the separate innervation of the periphery by the two major groups of OC neurons. It is also now clear that both of these groups consist of distinct subgroups. There is additional information on the reflex pathways leading up to OC neurons that enables their response to sound. Overall, this anatomy may help to define the functions that OC neurons perform in the sense of hearing.


Hair Cell Cochlear Nucleus Auditory Nerve Fiber Lateral Superior Olive Inner Hair Cell 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



I thank Dr. M. Charles Liberman for comments on the manuscript and Ms. Marie Drottar for assistance with the figures. This work was Supported by NIH grant DCD 01089.


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Authors and Affiliations

  1. 1.Department of Otology and LaryngologyHarvard Medical SchoolBostonUSA
  2. 2.Eaton-Peabody LaboratoryMassachusetts Eye and Ear InfirmaryBostonUSA

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