The lateral cervical nucleus of the Japanese monkey (<i>Macaca fuscata</i>)

Abstract

Abstract Based on the normal histological findings and the organization of the spinal afferents revealed by the Nauta and the Marchi methods, a cell group corresponding to the lateral cervical nucleus (NCL) of the cat was identified in the first and the second cervical segments of the spinal cord of the Japanese monkey ( Macaca fuscata ). The nucleus begins to appear at the level of the caudal end of the gracile nucleus and gradually disappears within the caudal half of the second cervical segment of the cord. The nucleus consists of medium‐sized and small‐sized nerve cells and receives spinal afferents ascending through the lateral funiculus, probably chiefly through the posterior spino‐cerebellar tract, from lower levels of the spinal cord. The spinal afferents seem to take origin entirely, or at least chiefly, from the ipsilateral spinal gray and to terminate in the nucleus without any localization. Some problems concerning the lateral cervical nucleus as the site of the spino‐thalamic tract have also been discussed from the point of view of comparative anatomy.