The Nikon MicroscopyU confocal microscopy image gallery was created with a PCM-2000 confocal scanning system interfaced to a Nikon Eclipse E600 upright microscope. Images were recorded in successive z-axis serial sections with C-Imaging Systems software with excitation illumination provided by an argon-ion and/or a helium-neon laser.

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The cerebellum is the portion of the human hindbrain that ensures a movement goes where it is supposed to go, at a proper rate and with a force appropriate to the resistance being overcome. By comparing information received by the eyes, body parts and the cerebrum, the cerebellum calculates when a motion should be slowed and ultimately stopped. In order to comb your hair while looking in a mirror, your brain must send its intent to the proper skeletal muscles, process what it sees in the reflection (the reverse of reality), and ensure you are doing what you want to do by correction and error control. All this occurs rapidly at the subconscious level in the cerebellum.

When waving your hand from left to right, your hand pivots at the wrist in a swinging motion like a pendulum with every movement, opposed by a force in the opposite direction. Because of the opposing body movements typical of the human body, there is a tendency for tremor, a more rapid back and forth motion. The cerebellum is able to dampen or cancel the tremor, resulting in smoother motion. If a movement such as serving a tennis ball is to be accurate and purposeful, particular groups of muscles must be made to contract in a particular order and this progression of muscles is driven by the cerebellum. If a person had to think out each and every muscle movement, he really couldn't play tennis very well. Disorders of the cerebellum interfere with its four functions: error control, damping, prediction, and progression.

About the size of a human fist, the cerebellum is the only branch of the brain between its inline division going from the spinal cord to the cerebral cortex. There is extensive folding of the thin, outer cortex into folia, and animals with more folia tend to have better motor coordination. A great mass of myeliniated axons (white matter), internal to the cortex, converge at the cerebellum core, the central medullary body. Within the core are a pair of deep cerebellar nuclei. The three layers of the cerebellar cortex are the inner granular layer (which contains mostly granular cells plus the cell bodies of Golgi cells), the middle Purkinje layer (which only contains Purkinje cells), and the outer molecular layer (which includes the stellate and basket cells).