Optokinetic reactions during free head rotations.
In order to study the effects of head rotations on optokinetic responses, we compared optokinetic nystagmus on gaze recordings between pursuits with the head fixed, with fixed-head oscillations and with the head free. Although subjects could perceptionally well pursue stripes even at 120 and 150 degrees/sec in case of pursuits with the head free, while fixed-head oscillations inhibited trackings, we could not find a significant difference of pursuit gaze speed among the different conditions. The result indicates that pursuit gaze speed is decided exclusively by the stripe speed, irrespective of head movements, and that the most important factor to decide perception is the pursuit angle of the tracked stripes rather than the pursuit speed.
D000293:Adolescent; D000328:Adult; D004584:Electronystagmography; D005133:Eye Movements; D006257:Head / Q000033:anatomy & histology / Q000502:physiology*; D006801:Humans; D009991:Oscillometry; D012399:Rotation