Cross-section of human cerebellum. The cerebellum (Latin for little brain) is the region of the brain that helps integrate perception, coordination and motor control. Neural pathways link the cerebellum to the cerebral motor cortex, which sends signals to the muscles to move, and to the spinocerebellar tract which allows the body to position itself properly in space. provides (proprioceptive feedback). The cerebellum takes up only 10% of the brain's volume, but it contains more than 50% of the brains neurons. The cerebellum receives nearly 200 million input fibers; in contrast, the optic nerve is composed of a mere one million fibers. In humans, the cerebellum plays an important role in motor control, and it may also be involved in some cognitive functions such as attention and language as well as in regulating fear and pleasure responses, but its movement-related functions are the most solidly established.