Brainstem control of horizontal gaze

Only excitatory pathways are shown; inhibitory pathways exist as well. Final common pathways for all horizontal eye movements are shown as thick black arrows. Saccadic commands (blue) are generated in the ipsilateral parapontine reticular formation. Excitatory vestibular input is generated in the contralateral horizontal semicircular canal, synapses in the medial vestibular nucleus, and projects directly to the VI nucleus. Pursuit inputs from the dorsolateral pontine nucleus decussate to the flocculus and project to the medial vestibular nucleus as well. (Contributed by Dr. Jason Barton.)