| Superior colliculus | Midbrain structure critical for initiating saccades, with separate maps for vertical and horizontal movements |
| Reticular formation | Contains burst neurons that trigger saccades and pause neurons that inhibit them |
| Posterior commisure | Acts as a conduit for vertical saccade signals |
| Interstitial nucleus of Cajal | Involved in vertical gaze holding and torsional movements |
| Downgaze typically affected first | patients have difficulty looking downward |
| Upgaze affected later | progression to involve upward gaze |
| Databases | OMIMOrphanetClinicalTrialsPubMed |