Observations on Structure and Function of the Olivocochlear Projections in Cat

  • M. Charles Liberman
Conference paper
Part of the Lecture Notes in Biomathematics book series (LNBM, volume 87)


The efferent projections to the inner ear are composed of two fundamentally different fiber types [Warr and Guinan, ’79]: a system of relatively large myelinated fibers whose major peripheral target is the bases of outer hair cells (OHCs) [Kimura and Wersall, ’62] and a system of smaller. unmyelinated fibers which project mainly to the dendrites of afferent fibers in the region under the inner hair cells (OHCs) [Smith, ’61], as schematized in Figure I. In addition, to these “classic” terminals of the olivocochlear bundle (OCB), there are a number of reports in the literature of other vesiculated terminals within the organ of Corti which may also be derived from the OCB [Ginzberg and Morest, ’84; Hashimoto et al., ’90; Bredberg, ’77]. In most previous studies of OC projections, electron microscopic (EM) analysis has been used to distinguish afferent from efferent terminals. Due to the inherent sampling limitations of EM studies, the cochlear distribution of the various vesiculated terminals has never been systematically described.


Auditory Nerve Outer Hair Cell Efferent Terminal Efferent Innervation Classic Terminal 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • M. Charles Liberman
    • 1
    • 2
  1. 1.Departments of Otolaryngology and PhysiologyHarvard Medical SchoolBostonUSA
  2. 2.Eaton-Peabody LaboratoryMassachusetts Eye and Ear InfirmaryBostonUSA

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