Covert saccades
This is an example of head impulse data that exhibits an abnormal vestibular ocular reflex on the
right
side indicated by
the gain response and the catch-up saccades. Looking at the Gain graph the data points are all within the gray range indic-
ating unilateral loss. Note the asymmetry of 56%. The right (abnormal) side is affecting the left (normal) side. The head data
shows well performed head impulses and the eye data shows an inadequate vestibular ocular reflex (A) that does not mir-
ror the head velocities. There are covert catch-up saccades present (B). Notice how the covert catch-up saccades are closer
to the head data whereas the overt catch-up saccades were further to the right of the head data.
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Otometrics - ICS Impulse USB
9 Head Impulse