Summary
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1.
Neurones in the lateral reticular nucleus (LRN) activated by the bilateral ventral flexor reflex tract (bVFRT-LRN neurones) were identified by their responses to stimulation of fibres descending in the contralateral ventral quadrant of the spinal cord which activate the bVFRT neurones monosynaptically.
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2.
Eighty-eight of the 134 bVFRT-LRN neurones encountered could be antidromically activated at a low stimulus strength from small areas of the cerebellar surface assumed to represent cortical termination points.
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3.
The bVFRT-LRN neurones occurred throughout the parvi- and magnocellular parts of the LRN and terminated bilaterally in the anterior lobe and sparsely in the ipsilateral paramedian lobule and in the pyramis.
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4.
The responses evoked in the bVFRT-LRN neurones on stimulation of the contralateral ventral quadrant at C5 and L1 made it possible to estimate the approximate spinal level from which the bVFRT fibres originated. On this basis the bVFRT-LRN neurones were divided into cervical, thoracic, and lumbar groups receiving bVFRT afferents from mainly one spinal level and a convergence group receiving bVFRT afferents from several levels.
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5.
The different bVFRT-LRN groups received excitation from different combinations of nerves in the four limbs.
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6.
The cervical, thoracic and lumbar groups of the bVFRT-LRN neurones occurred in successively more ventrolateral portions of the LRN.
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7.
The cervical, thoracic and lumbar groups of the bVFRT-LRN neurones terminated in successively more rostral areas of the anterior lobe.
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8.
The organization of the bVFRT-LRN path is compared with that of the ventral and rostral spinocerebellar tracts. The possible function of the bVFRT-LRN path is discussed.
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Clendenin, M., Ekerot, C.F., Oscarsson, O. et al. The lateral reticular nucleus in the cat II. Organization of component activated from bilateral ventral flexor reflex tract (bVFRT). Exp Brain Res 21, 487–500 (1974). https://doi.org/10.1007/BF00237167
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DOI: https://doi.org/10.1007/BF00237167