Effect of state on nystagmus duration in the Southern California Postrotary Nystagmus Test.

The purpose of this study was to determine the effect of state on nystagmus duration following administration of the Southern California Postrotary Nystagmus Test (SCPNT). Twenty-four normal children, 12 first-graders and 12 fourth-graders, were administered with SCPNT under three conditions: aroused, relaxed, and alert (standard instructions). Six boys and six girls in each grade participated. First-grade boys and fourth-grade girls demonstrated a statistically significant response decline in the aroused conditions, and a further decline in the relaxed condition as compared to the alert condition. Further analyses demonstrated that the first-grade boys accounted for most of the variance. Possible reasons for the results obtained are discussed, and suggestions are made for future research.