Timothy C. Hain, MD Page last modified: June 18, 2009
The RiMLF stands for the rostral interstitial nucleus of the median longitudinal fasciculus. It contains short latency burst neurons for vertical and torsional saccades and generates premotor neural drive for vertical and ipsiversive torsional fast eye movements. Unilateral riMLF lesions produce contraversive torsional nystagmus, slowed and limited vertical saccades, and loss of ipiversive torsional nystagmus during torsional rotation.
The INC stands for the Instersitial nucleus of Cajal. It is the neural integrator for vertical and torsional eye movements. Lesions of the INC cause ipsiversal torsional nsytagmus, decreased gaze-holding for vertical and torsional saccades, and reduced range of vertical saccades without slowing. INC lesions can also cause see-saw nystagmus.
Both of these structures are at the top of the midbrain, and both of these structures provide premotor control of vertical and torsional eye movements.