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Acta Biologica Hungarica

, Volume 55, Issue 1–4, pp 211–220 | Cite as

Regulation of Afferent Transmission in the Feeding Circuitry of Aplysia

  • Elizabeth C. CropperEmail author
  • C. G. Evans
  • J. Jing
  • A. Klein
  • A. Proekt
  • A. Romero
  • S. C. Rosen
Article

Abstract

Although feeding in Aplysia is mediated by a central pattern generator (CPG), the activity of this CPG is modified by afferent input. To determine how afferent activity produces the widespread changes in motor programs that are necessary if behavior is to be modified, we have studied two classes of feeding sensory neurons. We have shown that afferent-induced changes in activity are widespread because sensory neurons make a number of synaptic connections. For example, sensory neurons make monosynaptic excitatory connections with feeding motor neurons. Sensori-motor transmission is, however, regulated so that changes in the periphery do not disrupt ongoing activity. This results from the fact that sensory neurons are also electrically coupled to feeding interneurons. During motor programs sensory neurons are, therefore, rhythmically depolarized via central input. These changes in membrane potential profoundly affect sensori-motor transmission. For example, changes in membrane potential alter spike propagation in sensory neurons so that spikes are only actively transmitted to particular output regions when it is behaviorally appropriate. To summarize, afferent activity alters motor output because sensory neurons make direct contact with motor neurons. Sensori-motor transmission is, however, centrally regulated so that changes in the periphery alter motor programs in a phase-dependent manner.

Keywords

Invertebrate central pattern generator sensori-motor integration mollusc feeding 

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© Akadémiai Kiadó, Budapest 2004

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Authors and Affiliations

  • Elizabeth C. Cropper
    • 1
    Email author
  • C. G. Evans
    • 1
  • J. Jing
    • 1
  • A. Klein
    • 1
  • A. Proekt
    • 1
  • A. Romero
    • 1
  • S. C. Rosen
    • 1
  1. 1.Department of Physiology and BiophysicsMt. Sinai School of MedicineNew YorkUSA

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