ORGANIZATION OF BILATERAL SPINAL PROJECTIONS TO THE LATERAL RETICULAR NUCLEUS OF THE RAT

摘要

Recent works on patients with unilateral cerebellar lesions show changes in kinematics of contralateral limbs with reduction of the peak speed and slowing of pointing movements (7). Recently, Greger et al. (3) observed that the activity of neurons of the lateral cerebellum are dependent on variation of movement parameters, independently of the used limb. On the basis of their results, these Authors suggested the possibility of a gradient for the effects elicited by contralateral inputs, with a minimal action in the more medial part of the cerebellum and increasing influences on the more lateral parts. Concerning the possible pathways mediating these bilateral inputs, the lateral reticular nucleus (LRN) could represent a solid candidate. As matter of fact, data available from investigations in different mammals indicate that the main afferent inputs to the LRN are a bilateral, topographically organized projection from the spinal cord (for review, see 1 8). Furthermore, the projections from LRN to the cerebellum are bilateral, with an ipsilateral predominance (PI4), and they involve both anterior and posterior cerebellar lobes (23,25).