Section of the Brain
The cerebellum is a structure attached at the bottom-rear of the brain, below the cerebrum, and at the back of the brain stem. Like the cerebral cortex, the cerebellum is divided into two hemispheres. The surface of the cerebellum appears to have many narrow, parallel groves. This is because the cerebellum is actually a thin layer of neural tissue tightly folded like an accordion. This folding upon itself allows the cerebellum to contain more neurons than the rest of the brain put together, in only 10% of total brain volume.
The cerebellum is involved in movement and motor control. It does not initiate movement, but it is helps with coordination, precision and timing of motor movements. The cerebellum receives input from sensory systems and from other parts of the brain and spinal cord, and integrates these inputs to fine tune motor activity. Cerebellum function is most obvious when there is damage to this part of the brain. A person with damage to the cerebellum can still generate motor activity, but loses precision. The result is erratic, uncoordinated, or incorrectly timed movements.
The cerebellum is also involved in some cognitive functions such as language, attention and mental imagery. It may also be involved in some emotional functions, such as regulating fear and pleasure responses.
Damage to the cerebellum can result in movements that are slow and uncoordinated, and a wide variety of muscle movement coordination problems. For example, movement problems such as staggering while walking and the tendency to fall, difficulty in judging distance and when to stop, slurred speech, and abnormal eye movements.