Lab 9 - Descending Pathways to the Spinal Cord

Clinical Correlate-Lesions of the Red Nucleus

Some cells of the red nucleus receive fibers from the precentral gyrus of the cerebral cortex and send fibers in the rubrospinal tract to the spinal cord. Thus, the corticorubral and rubrospinal tracts constitute a non-corticospinal pathway from the motor cortex to the spinal cord.

It has been suggested that this path might be involved in coordinating discrete voluntary movement of the limbs and digits. There have been a few cases of circumscribed lesions in the red nucleus without involvement of surrounding midbrain structures. These patients were described to have some degree of contralateral hemiparesis, occasionally with somewhat exaggerated tendon reflexes and weakened abdominal reflexes.