Journal of Neurophysiology, Vol 38, Issue 2 332-346, Copyright © 1975 by APS
Analysis of postural motoneuron activity in crayfish abdomen. II. Coordination by excitatory and inhibitory connections between motoneurons
W. G. Tatton and P. G. Sokolove
The identified spike trains of the crayfish abdominal postural efferent
neurons were recorded simultaneously from one or more segments. The
efferent activity was analyzed using cross-correlation histograms,
peristimulus time scatter diagrams, and specialized antidromic techniques.
The analyses show that the larger, phasically active motoneurons are
coordinated in their activity by cross connections made at the motoneuron
level. The cross connections are both excitatory and inhibitor in nature
and result in significant alterations in spike output. Further, the
accessory neuron receives an inhibitory cross connection from a
middle-sized extensor excitor motoneuron or motoneurons. In each case, the
cross connections appear to be appropriate to the function of the postural
system.
