Observations on the physiology of the otic labyrinth. The influence of prolonged rotation on the duration of postrotatory nystagmus

Abstract

Rotation of the head in space is accompanied by ocular movements of a definite type. These ocular movements (nystagmus) present two phases: a slow deviation of the eyes opposite to the direction of rotation, followed by a quick return to the initial position.On cessation of rotation similar movements are observed. In the post-rotatory nystagmus, however, the slow deviation phase is in the direction of the preceding rotation.The deviation phase as shown by Wilson and Pike1 is dependent on labyrinthine stimulation whereas the quick return is due to a proprioceptor reflex arising from the stretched antagonist ocular muscle during the deviation phase. These ocular movements can be especially well studied in the post-rotatory period.The duration of the post rotatory nystagmus is dependent on the intensity of the labyrinthine stimulus and therefore on the speed of rotation and up to a certain point on the number of revolutions at any given speed. Using a standard of ten turns in twenty seconds, the duration of ...