Development of the nervous system in humans optical vesicle (which will eventually become the optic nerve, retina and iris) forms at the basal plate of the prosencephalon. In the fifth week, the alar plate of the prosencephalon expands to form the cerebral hemispheres (the telencephalon). The basal plate becomes the diencephalon. The diencephalon, mesencephalon and rhombencephalon constitute the brain stem of the embryo. It continues to flex at the mesencephalon. The rhombencephalon folds posteriorly, which causes its alar plate to flare and form the fourth ventricle of the brain. The pons and the cerebellum form in the upper part of the rhombencephalon, whilst the medulla oblongata forms
Anatomy of the cerebellum pathway transmits signals that inform the cerebellum about the movement in progress and the upcoming movement. This helps the continuous adjustment of motor activity. The initiation of the movement is relayed to cerebellum via the corticoreticulocerebellar pathway. Those synapse ipsilaterally in the reticular formation, then via the inferior and middle peduncles into the cerebellar vermis. The motor cortex and somatosensory cortex projects onto the ipsilateral inferior and accessory olivary nuclei, then forming the olivocerebellar tract. Cortico-olivary fibers synapse bilaterally in the inferior olivary nucleus. The order is preserved in the olivocerebellar tract projections onto the ‘body maps’ in the contralateral