Effects of Frequency and Sex on Measures of Gain, Phase, and Asymmetry in Sinusoidal Harmonic Acceleration

Professionals rely on established clinical standards and best clinic guidelines during vestibular testing to ensure the collection of accurate data. The most direct and practical way to analyze and evaluate the peripheral vestibular system is through ocular motility testing (Jacobson & Shepard, 2016). The objective of this study was to establish normative data using standard protocols and parameters of the associated clinical subtest, Sinusoidal Harmonic Acceleration (SHA), using the NeuroKinetics (NOTC) rotational chair. SHA measures of gain, phase, and asymmetry were recorded from thirty-four participants aged 18-28 with normal functioning vestibular systems. These measures were obtained at seven testing frequencies: 0.01 Hz, 0.02, 0.04, 0.08, 0.16, 0.32, and 0.64 Hz at a peak velocity of 60 degrees/second. Two, two-way repeated measures analysis of variance (ANOVA) were conduct-ed post data collection to compare the effects of frequency and sex on measures of vestibular-oc-ular reflex (VOR) gain, phase, and asymmetry. The results of this study found no statistical significance on measures of gain, phase, and asymmetry between seven tested octave frequencies. Additionally, no statistical difference was found in the measures of gain, phase, and asymmetry between male and female participants.