Connections between Cerebellum and Spinal Cord

Connections between Cerebellum and Spinal Cord

     From a clinical point of view the most important connections of the cerebellum are with the spinal cord, and with the cerebral cortex. These connections are through various pathways that are summarised below.

        Spinocerebellar pathways convey to the cerebellum proprioceptive information necessary for controlling muscle tone and for maintaining body posture. These pathways also carry exteroceptive impulses.

Direct pathways from spinal cord to cerebellum

       These are the ventral spinocerebellar tract, and the dorsal spinocerebellar tract which convey information from the hind limb. Information from the forelimb is probably conveyed by the rostral spinocerebellar tract and the cuneocerebellar tract. The cuneocerebellar tract begins in the medulla, but is included here as it is functionally equivalent to spinocerebellar tracts.

Indirect pathways from spinal cord to cerebellum

These are:

(a) Spino-olivo-cerebellar;      

(b) Spino-reticulo-cerebellar;  

(c) Spino-vestibulo-cerebellar; and

(d) Spino-tecto-cerebellar pathways.

           Although these are not concerned with the spinal cord it is useful to consider here the pathways that carry impulses from tissues in the head to the cerebellum. Exteroceptive impulses from the head (and parts of the neck) reach the cerebellum through trigemino-cerebellar fibres arising in the main sensory and spinal nuclei of this nerve. Fibres from the mesencephalic nucleus convey proprioceptive information from the muscles of mastication to the cerebellum.

Cerebello-spinal pathways

           Although the presence of some direct cerebellospinal fibres has been claimed, their existence is not established. The cerebellum can, however, influence the spinal cord through the following pathways:

(a) Cerebello-rubro-spinal;

(b) Cerebello-vestibulo-spinal;

(c) Cerebello-reticulo-spinal;

(d) Cerebello-tecto-spinal; and

(e) Cerebello-thalamo-cortico-spinal.