Suppression of caloric nystagmus by virtual stare

Abstract

　[Introduction] I conducted this experiment to examine whether virtual stare can suppress nystagmus.

　[Subjects] Twelve healthy adult volunteers (total 24 ears).

　[Method] The experiment was conducted as follows:

　1. Subjects wearing a video-oculograhic apparatus for nystagmus

　　measurement underwent a caloric test, and nystagmus was recorded.

　2. When the slow-phase velocity of the nystagmus reached its maximum

　　value, the subjects were told/asked the following: “A dim light is lit at

　　the same place as that in the visual suppression test. Please gaze at the

　　light. What color is it now?” No light was actually lit.

　3. After 10 seconds, they were instructed to stop looking (unable to see

　　in reality).

　[Results] The mean slow-phase velocity of the caloric nystagmus decreased significantly during the load (stimulation) (p<0.01). The mean slow-phase velocity during the 10 seconds prior to the load (stimulation) was 12.4±3.3°/s, and that during the load (stimulation) was 8.1±2.7°/s. The nystagmus suppression rate was 33.2±18.0%.

　[Summary] The study suggested that virtual stare suppressed peripheral nystagmus.