Fig. 6. Central connections of the utricle mediating the ocular tilt reflex. This figure illustrates the projections from the right utricle. Primary afferents of the utricle project to the lateral (L) and medial (M) vestibular nuclei. Neurons in the lateral vestibular nucleus cross the midline and travel up the medial longitudinal fasiculus (MLF) to project to the IVth and IIIrd nerve nuclei, which innervate eye muscles involved with vertical and torsional eye movements. The IIIrd nerve nucleus also innervates the interstitial nucleus of Cajal (INC). The INC in turn projects back to the IIIrd and IVth nerve nuclei. Neurons in the L and M vestibular nucleus also project to the spinal cord through the lateral and medial vestibular spinal tracts (LVST and MVST).