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.
Skip Nav Destination
Article navigation
1 March 1962
Article|
March 01 1962
Spontaneous Activity in Crustacean Neurons
James B. Preston,
James B. Preston
From The Department of Physiology, Upstate Medical Center, State University of New York, Syracuse, and the Department of Zoology, Syracuse University.
Search for other works by this author on:
Donald Kennedy
Donald Kennedy
From The Department of Physiology, Upstate Medical Center, State University of New York, Syracuse, and the Department of Zoology, Syracuse University.
Search for other works by this author on:
James B. Preston
From The Department of Physiology, Upstate Medical Center, State University of New York, Syracuse, and the Department of Zoology, Syracuse University.
Donald Kennedy
From The Department of Physiology, Upstate Medical Center, State University of New York, Syracuse, and the Department of Zoology, Syracuse University.
Dr. Kennedy's present address is the Department of Biological Sciences, Stanford University, Stanford, California
Received:
November 24 1961
Online ISSN: 1540-7748
Print ISSN: 0022-1295
Copyright, 1962, by The Rockefeller Institute Press
1962
J Gen Physiol (1962) 45 (4): 821–836.
Article history
Received:
November 24 1961
Citation
James B. Preston, Donald Kennedy; Spontaneous Activity in Crustacean Neurons . J Gen Physiol 1 March 1962; 45 (4): 821–836. doi: https://doi.org/10.1085/jgp.45.4.821
Download citation file:
Sign in
Don't already have an account? Register
Client Account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
Sign in via your Institution
Sign in via your InstitutionSuggested Content
Inhibition of Impulse Activity in a Sensory Neuron by an Electrogenic Pump
J Gen Physiol (February,1971)
THE VITAMIN A OF A EUPHAUSIID CRUSTACEAN
J Gen Physiol (March,1957)
Correlated Electrophysiological and Ultrastructural Studies of a Crustacean Motor Unit
J Gen Physiol (May,1972)
Email alerts
Advertisement