Use the drop-down menus to complete the sentences. Motor neurons are the neurons that carry signals from the brain to the , enabling voluntary movement. The corticospinal tract is a tract of neurons that descends from the , crosses over in the brain stem, and then connects with motor neurons in the spinal cord. The spinal cord is nervous tissue that connects the brain to the . The cranial nerve is a nerve that connects to the CNS at the rather than at the spinal cord. The primary motor cortex is the region of the that controls the voluntary muscles on the opposite side of the body.