Aim. Ocular Evoked Myogenic Potential (oVEMP) are short latency potentials evoked by higher acoustic stimulation. In this study, we aimed at comparing the click, 500？Hz mixed modulated, and 500？Hz short duration tone burst stimuli using oVEMP. Material. Click, 500？Hz mixed modulated and 500？Hz short duration tone burst stimuli were used for the study. Method. Conventional sampling and conveneint study design were used. Sixty healthy subjects underwent contralateral oVEMP testing maintaining 30 degrees upward gaze. Single channel electrode montage was applied to record oVEMP response. Results. On statistical analysis the three stimuli evoked equal response rates (100%), and when latency of n1 and p1 and peak-peak amplitude were compared, the click evoked showed significantly early latency and lower peak-peak amplitude than the 500？Hz stimuli. Five hundred Hz stimuli did not show significant difference in latency and peak-peak amplitude of n1-p1. Discussion. Thus, 500？Hz stimuli can evoke better latency and peak-peak amplitude. oVEMP has good clinical significance in diagnosing subjects with vestibular dysfunction. To add to the sensitivity of the oVEMP test, 500？Hz stimuli may also be used as it can evoke better oVEMP responses in clinical population with good morphology. 1. Introduction Human auditory system consists of otolith, namely, saccule and utricle. Vestibular evoked myogenic potential (VEMP) is one of such tests which checks function of otolith organ. VEMP can be elicited by placing the electrodes on different contracted muscles and hence the names cervical VEMP and ocular VEMP. These are electromyogenic short latency electrical impulses recorded using high acoustic stimuli. It is a proposed reliable test of saccular or inferior vestibular nerve function. In human, a vestibulo-ocular reflex stabilizes the visible world upon the retina during head and body movements. The cervical vestibular evoked myogenic potential (cVEMP) assesses the descending vestibular pathway as ipsilateral sacculocollic reflex; [1] reported the ocular vestibular evoked myogenic potential (oVEMP) to evaluate the ascending vestibular pathway as crossed vestibulo-ocular reflex. They also premised that binaural acoustic stimulation can elicit oVEMPs as effectively as monaural acoustic stimulation does. The former method requires more muscular effort than the later since continuous upward gazing is necessary during oVEMP testing. Normal cVEMP responses are characterized by biphasic (positive-negative) waves. The first peak is denoted as p1 followed by n1. Peaks in cVEMP are
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