Abstract
It has been difficult to predict the behavioral roles of vertebrate CNS neurons based solely on their morphologies, especially for the neurons that control limb movements in adults. We examined the morphologies of spinal interneurons involved in limb movement control, using intracellular recording followed by Neurobiotin injection in the in vivo adult turtle spinal cord preparation. We report here the first description of a class of spinal interneurons whose somato-dendritic morphologies predict their robust activity during multiple forms of ipsilateral and contralateral fictive hindlimb scratching and fictive hindlimb withdrawal. These "transverse interneurons" or T cells have mediolaterally elongated soma and a simple dendritic tree that is extensive in the transverse plane but restricted rostrocaudally. During fictive scratching, these cells display strong rhythmic modulation with higher peak firing rates than other scratch-activated interneurons. These higher peak firing rates are at least partly caused by T cells having larger phase-locked membrane potential oscillations and narrower action potentials with briefer afterhyperpolarizations than other scratch-activated interneurons. Many T cells have axon terminal arborizations in the ventral horn of the spinal cord hindlimb enlargement. Identification of this morphological and physiological class of spinal interneurons should facilitate further exploration of the mechanisms of hindlimb motor pattern selection and generation. Copyright © 2006 The American Physiological Society.
Recommended Citation
A. Berkowitz et al., "Somato-dendritic Morphology Predicts Physiology for Neurons that Contribute to Several Kinds of Limb Movements," Journal of Neurophysiology, vol. 95, no. 5, pp. 2821 - 2831, American Physiological Society, May 2006.
The definitive version is available at https://doi.org/10.1152/jn.01246.2005
Department(s)
Biological Sciences
Publication Status
Open Access
International Standard Serial Number (ISSN)
0022-3077
Document Type
Article - Journal
Document Version
Final Version
File Type
text
Language(s)
English
Rights
© 2025 American Physiological Society, All rights reserved.
Creative Commons Licensing
This work is licensed under a Creative Commons Attribution 4.0 License.
Publication Date
01 May 2006
PubMed ID
16452255
