Spontaneous Activity in Crustacean Neurons
Single units which discharged with regular spontaneous rhythms without intentional stimulation were observed in the ventral nerve cord by intracellular recording close to the sixth abdominal ganglion. These units were divided into two groups: group A units in which interspike intervals varied less...
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| Format: | Online |
| Language: | English |
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The Rockefeller University Press
1962
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| Online Access: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2195199/ |
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pubmed-2195199 |
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pubmed-21951992008-04-23 Spontaneous Activity in Crustacean Neurons Preston, James B. Kennedy, Donald Article Single units which discharged with regular spontaneous rhythms without intentional stimulation were observed in the ventral nerve cord by intracellular recording close to the sixth abdominal ganglion. These units were divided into two groups: group A units in which interspike intervals varied less than 10 msec.; group B units in which interspike intervals varied within a range of 10 to 30 msec. Group A units maintained "constant" interspike intervals and could not be discharged by sensory inputs, while the majority of group B units could be discharged by appropriate sensory nerve stimulation. Both group A and B units discharged to direct stimulation when the stimulating and recording electrodes were placed in the same ganglionic intersegment, and directly evoked single spikes reset the spontaneous rhythm. In group B units, presynaptic volleys reset the spontaneous rhythm of some units; but in others, synaptically evoked spikes were interpolated within the spontaneous rhythm without resetting. The phenomenon of enhancement could also be demonstrated in spontaneously active units as a result of repetitive stimulation. It is concluded that endogenous pacemaker activity is responsible for much of the regular spontaneous firing observed in crayfish central neurons, and that interaction of evoked responses with such pacemaker sites can produce a variety of effects dependent upon the anatomical relationships between pacemaker and synaptic regions. The Rockefeller University Press 1962-03-01 /pmc/articles/PMC2195199/ /pubmed/14488667 Text en Copyright © Copyright, 1962, by The Rockefeller Institute Press This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
| repository_type |
Open Access Journal |
| institution_category |
Foreign Institution |
| institution |
US National Center for Biotechnology Information |
| building |
NCBI PubMed |
| collection |
Online Access |
| language |
English |
| format |
Online |
| author |
Preston, James B. Kennedy, Donald |
| spellingShingle |
Preston, James B. Kennedy, Donald Spontaneous Activity in Crustacean Neurons |
| author_facet |
Preston, James B. Kennedy, Donald |
| author_sort |
Preston, James B. |
| title |
Spontaneous Activity in Crustacean Neurons |
| title_short |
Spontaneous Activity in Crustacean Neurons |
| title_full |
Spontaneous Activity in Crustacean Neurons |
| title_fullStr |
Spontaneous Activity in Crustacean Neurons |
| title_full_unstemmed |
Spontaneous Activity in Crustacean Neurons |
| title_sort |
spontaneous activity in crustacean neurons |
| description |
Single units which discharged with regular spontaneous rhythms without intentional stimulation were observed in the ventral nerve cord by intracellular recording close to the sixth abdominal ganglion. These units were divided into two groups: group A units in which interspike intervals varied less than 10 msec.; group B units in which interspike intervals varied within a range of 10 to 30 msec. Group A units maintained "constant" interspike intervals and could not be discharged by sensory inputs, while the majority of group B units could be discharged by appropriate sensory nerve stimulation. Both group A and B units discharged to direct stimulation when the stimulating and recording electrodes were placed in the same ganglionic intersegment, and directly evoked single spikes reset the spontaneous rhythm. In group B units, presynaptic volleys reset the spontaneous rhythm of some units; but in others, synaptically evoked spikes were interpolated within the spontaneous rhythm without resetting. The phenomenon of enhancement could also be demonstrated in spontaneously active units as a result of repetitive stimulation. It is concluded that endogenous pacemaker activity is responsible for much of the regular spontaneous firing observed in crayfish central neurons, and that interaction of evoked responses with such pacemaker sites can produce a variety of effects dependent upon the anatomical relationships between pacemaker and synaptic regions. |
| publisher |
The Rockefeller University Press |
| publishDate |
1962 |
| url |
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2195199/ |
| _version_ |
1611431905689862144 |