Table 1.
Key Terms in Ocular Motor Research, Examinations and Analysis and Their Definitions
| Term | Definition |
|---|---|
| Catch Up Saccades | Rapid eye movements to adjust the eye’s position to refocus following a head movment as part of a faulty vestibulo-ocular reflex. |
| Convergence | Eye movements where the eyes move inward, towards each other. |
| Divergence | Eye movements where the eyes move outward, away from each other. |
| Drift | Slow, involuntary eye movements during attempted fixation. |
| Electro-oculography | Measuring eye movements by detecting electrical potentials. |
| Error Rate | The frequency of errors in reaching the target during eye movements. |
| Fixation | Maintenance of the gaze on a single location. |
| Hypermetric | Saccades that overshoot the intended target. |
| Hypometric | Saccades that fall short of the intended target. |
| Infrared Oculography | Tracking eye movements using infrared light. |
| Latency | The delay between the initiation and the onset of an eye movement. |
| Microsaccades | Small, involuntary eye movements during fixation to refresh the image on the retina. |
| Nystagmus | Involuntary, rhythmic oscillation of the eyes, often indicating underlying issues. |
| Pursuit | Smooth eye movements to track moving objects. |
| Pursuit Gain | The ratio of eye velocity to target velocity during pursuit movements. |
| Pursuit Speed | The speed at which the eye moves to follow a moving target. |
| Saccade | Rapid, ballistic eye movements to shift gaze from one point to another. |
| Saccade Accuracy | The precision of the eye in landing on the target during a saccade. |
| Saccade Peak Velocity | The highest speed reached by the eye during a saccade. |
| Saccade Speed | The average speed of the eye during a saccade. |
| Saccadic Bradykinesia | Decrement in the velocity and amplitude of repetitive horizontal saccades, often seen in Parkinson’s disease. |
| Saccadic Intrusions | Unwanted saccades that disrupt fixation. |
| Square Wave Jerks | Small, involuntary eye movements away from and back to the fixation point. |
| Ocular Tremor | Involuntary, rhythmic oscillation, affecting eye movements. |
| Video-oculography | Tracking eye movements using video imaging. |
| Vestibulo-ocular reflex | Mechanism that stabilizes vision by producing eye movements that counteract head movements, ensuring clear vision while in motion. |