Nonclassical Features of Dorsal Root Ganglion Cell Organization

  • Richard E. Coggeshall


Dorsal root ganglion cells and their cranial nerve equivalents are the primary sensory cells for general somatic sensation. The cell bodies of these neurons are located in dorsal root and certain cranial nerve ganglia. Each cell body is reported to give rise to a single stem process that branches into a proximal and a distal process, the proximal process entering the spinal cord through a dorsal root and the distal process passing to the periphery via a peripheral nerve. This organization is schematized in Figure 1, and similar pictures are seen in almost all texts dealing with the organization of the nervous system. This is an important scheme, for it imposes restraints on the way we reason about the transfer of somatic information centrally. In recent years, however, evidence has accumulated to indicate that two aspects of the above scheme are oversimplified. These are (1) that each dorsal root ganglion cell has a single process in the dorsal root and a single process in the peripheral nerve and (2) that the central processes of dorsal root ganglion cells travel only in the dorsal root. This report indicates how we arrived at the classic scheme and then presents the evidence indicating that the classic scheme needs modification. Some speculations as to the functional significance of these modifications are offered.


Spinal Cord Dorsal Root Ganglion Ganglion Cell Dorsal Root Ventral Root 
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Copyright information

© Springer Science+Business Media New York 1986

Authors and Affiliations

  • Richard E. Coggeshall
    • 1
  1. 1.Departments of Anatomy, Physiology, and BiophysicsUniversity of Texas Medical BranchGalvestonUSA

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