Anatomy of the cerebellum to the cerebellum, in two categories consisting of mossy and climbing fibers, respectively. Mossy fibers can originate from the pontine nuclei, which are clusters of neurons located in the pons that carry information from the contralateral cerebral cortex. They may also arise within the spinocerebellar tract whose origin is located in the ipsilateral spinal cord. Most of the output from the cerebellum initially synapses onto the deep cerebellar nuclei before exiting via the three peduncles. The most notable exception is the direct inhibition of the vestibular nuclei by Purkinje cells. During the early stages of embryonic development, the brain starts
Anatomy of the cerebellum the numerous and tiny granule cells, the slightly larger unipolar brush cells and the much larger Golgi cells. Mossy fibers enter the granular layer from their main point of origin, the pontine nuclei. These fibers form excitatory synapses with the granule cells and the cells of the deep cerebellar nuclei. The granule cells send their T-shaped axons—known as parallel fibers—up into the superficial molecular layer, where they form hundreds of thousands of synapses with Purkinje cell dendrites. The human cerebellum contains on the order of 60 to 80 billion granule cells, making this single cell type by far the most