Persistent Responses to Brief Stimuli: Feedback Excitation Among Brainstem Neurons.
From: School of Biological Sciences, University of Bristol, Bristol BS8 1UG, United Kingdom.
The Journal of neuroscience : the official journal of the Society for Neuroscience
- Publish Date: Apr 2006
- ISSN: 1529-2401
- Volume: 26
- Issue: 15
- Pages: 4026-35
- Medium: Internet
- Language: English
- Citation (JAMA): Li Wen-Chang, Soffe Stephen R, Wolf Ervin, et al. Persistent Responses to Brief Stimuli: Feedback Excitation Among Brainstem Neurons.. J. Neurosci. Apr 2006;26:4026-35
Abstract
The ability of brief stimuli to trigger prolonged neuronal activity is a fundamental requirement in nervous systems, common to motor responses and short-term memory. Bistable membrane properties and network feedback excitation have both been proposed as suitable mechanisms to sustain such persistent responses. There is now good experimental evidence for membrane bistability. In contrast, the long-standing hypotheses based on positive feedback excitation have yet to be supported by direct evidence for mutual excitatory connections between appropriate neurons. In young frog tadpoles (Xenopus), we show that a small region of caudal hindbrain and rostral spinal cord is sufficient to generate prolonged swimming in response to a brief stimulus. We used paired whole-cell patch recordings to identify hindbrain neurons in this region that actively excite spinal neurons to drive sustained swimming. We show directly that some of these hindbrain neurons make reciprocal excitatory connections with each other. We use a population model of the hindbrain network to illustrate how feedback excitation can provide a robust mechanism to generate persistent responses. Our recordings provide direct evidence for feedback excitation among neurons within a network that drives a prolonged response. Its presence in a lower brain region early in development suggests that it is a basic feature of neuronal network design.
Mesh Headings (Keywords): Animals, Axons, Brain Stem, Electric Stimulation, N-Methylaspartate, Neurons, Patch-Clamp Techniques, Potassium Channels, Sodium Channels, Software, Xenopus
Check for Full Text / PubMed Unique Identifier (PMID): 16611819
This abstract is part of PubMed, a service of the U.S. National Library of Medicine. PubMed includes more than 17 million citations from MEDLINE and other life science journals for biomedical articles. See Copyright and Disclaimers.
Linked medical terms appearing on this page are added by Healia to help readers find more information and are not part of the original PubMed document.
The data herein was last updated on July 8th, 2008 and may not reflect the most current and accurate data available from NLM.