The cerebellum is the area at the back and bottom of the brain, behind the brainstem (where the spinal cord meets the brain). It receives information from the sensory systems, the spinal cord, and other parts of the brain and then regulates motor movements. The cerebellum coordinates voluntary movements such as posture, balance, coordination, and speech, resulting in smooth and balanced muscular activity. It is also important for learning motor behaviors and coordination of eye movements. Diffuse atrophy of the cerebellum refers to a progressive and irreversible reduction in cerebellar volume. It is found in a wide variety of clinical scenarios. It can also result from a variety of causes including drugs (alcohol and/or certain medications) and neurodegenerative diseases.