Fastigial nucleus

Fastigial nucleus is the smallest and the oldest of the grey matter nuclei of the cerebellum which is embedded deep within the subcortical cerebellar white matter.

From outside to inside, the cerebellum comprises of a superficial layer of cerebellar cortex, which envelopes a central core of white matter. Various neuronal cell bodies aggregate within the white matter core, leading to the formation of four deep cerebellar nuclei. One of those four nuclei include the fastigial nucleus. The others being dentate, emboliform and globose nuclei.

The fastigial nucleus is the most medially placed deep cerebellar nucleus and forms part of the vestibulocerebellar neuronal circuitry. It receives balance-related information from the inner ear. Many of the afferent neurons from the inner ear synapse first in the vestibular nuclei (at the junction of pons and medulla) en-route to the fastigial nucleus. Efferents from the fastigial nucleus project back to the vestibular nuclei, forming a vestibulocerebellar neuronal loop. Since, the vestibular nuclei innervate the both the antigravity muscles through the vestibulospinal pathways and the extra-ocular nuclei via the medial longitudinal fasciculus, therefore, the fastigial nucleus–as part of the vestibulocerebellar neuronal circuitry–gets to play a significant role in maintaining balance of axial and truncal body musculature and adjusting eye movements with changes in body position. A lesion in fastigial nucleus could result in reduced control of axial and truncal body musculature in antigravity posture.