The cerebellum appears to be a separate structure attached to the bottom of the brain. The surface of the cerebellum is covered with finely spaced parallel grooves, which covers up the fact that the cerebellum is a continuous thin layer of neural tissue, tightly folded like an accordion. Within this layer are several types of neurons - and it is this complex network of neurons that allows them their massive signaling capability.
The cerebellum receives input from sensory systems, other parts of the brain, and the spinal cord and then uses this input to fine tune motor activity. Because of this fine-tuning function, if there is damage to the cerebellum, it does not cause paralysis, but instead produces disorders in fine movement, equilibrium, posture and motor learning.