You're at: The Cerebellum

The cerebellum is a brain region important for a number of motor and cognitive functions, including learning. It is found at the bottom rear of the head (the hindbrain), directly above the brainstem. Patients with cerebellar dysfunction have problems with precise movements, such as walking/balance, and hand and arm movements. Recent fMRI studies show that the cerebellum is also important for attention and time perception. Problems with the cerebellum may also play a role in cognitive disorders such as dyslexia and autism.


The Cerebellum as a Computer

Two main theories address the function of the cerebellum. One claims that the cerebellum functions as a regulator of the timing of movements. This has emerged from studies of patients whose timed movements are disrupted. The other claims that the cerebellum operates as a learning machine, encoding information like a computer. This was first proposed by Marr and Albus in the early 1970s. Like many controversies in biology, some of both of these claims is true. Studies of motor learning in the vestibulo-ocular reflex and eyeblink conditioning are demonstrating that timing and amplitude of learned movements are encoded by the cerebellum). The Marr-Albus model mostly attributes motor learning to a single plasticity mechanism, long-term depression of parallel fiber synapses.



The embryonic cerebellum develops from the superior dorsal aspect of the rhombencephalon. In the mature mammallian brain, the cerebellum comprises a distinct structure at the back of the brain. The cerebellum is of archipalliar phylogenetic origin, shared as a prototypical brain structure by animals from the most elementary to the most advanced.