Accessory cuneate nucleus
[2] The neurons of the ACN (as well as those of the lateral portion of the cuneate nucleus) are functionally homologous with the posterior thoracic nucleus; the cuneocerebellar fibers are therefore the upper body functional equivalent of the dorsal spinocerebellar tract.[1]: 445 Afferents of the ACN arise from muscle stretch receptors and skin touch receptors of the upper limb; they enter the spinal cord rostral to the posterior thoracic nucleus to ascend in the lateral portion of the cuneate fasciculus.[1]: 445 A minority of the fibers of the cuneate fasciculus thus synapse in the ACN.[1]: 431 Efferents of the ACN form the cuneocerebellar fibers that pass through the ipsilateral restiform body of the inferior cerebellar peduncle to terminate in the ipsilateral hemisphere of the cerebellum;[2] a few of its efferents do not join the cuneocerebellar fibers, instead ascending in the contralateral medial lemniscus to terminate in the thalamus.[1]: 445 2° (Spinomesencephalic tract → Superior colliculus of Midbrain tectum)