Abstract
Objective: This study aimed to identify differences in vestibulo-ocular reflex gain (VOR gain) and saccadic response in the suppression head impulse paradigm (SHIMP) between predictable and less predictable head movements, in a group of healthy subjects. It was hypothesized that higher prediction could lead to a lower VOR gain, a shorter saccadic latency, and higher grouping of saccades.</p>Methods: Sixty-two healthy subjects were tested using the video head impulse test and SHIMPs in four conditions: active and passive head movements for both inward and outward directions. VOR gain, latency of the first saccade, and the level of saccade grouping (PR-score) were compared among conditions. Inward and active head movements were considered to be more predictable than outward and passive head movements.</p>Results: After validation, results of 57 tested subjects were analyzed. Mean VOR gain was significantly lower for inward passive compared with outward passive head impulses (p < 0.001), and it was higher for active compared with passive head impulses (both inward and outward) (p <= 0.024). Mean latency of the first saccade was significantly shorter for inward active compared with inward passive (p <= 0.001) and for inward passive compared with outward passive head impulses (p = 0.012). Mean PR-score was only significantly higher in active outward than in active inward head impulses (p = 0.004).</p>Conclusion: For SHIMP, a higher predictability in head movements lowered gain only in passive impulses and shortened latencies of compensatory saccades overall. For active impulses, gain calculation was affected by short-latency compensatory saccades, hindering reliable comparison with gains of passive impulses. Predictability did not substantially influence grouping of compensatory saccades.</p>
Original language | English |
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Article number | 729081 |
Number of pages | 10 |
Journal | Frontiers in Neurology |
Volume | 12 |
DOIs | |
Publication status | Published - 22 Sept 2021 |
Keywords
- vestibular ocular reflex
- video head impulse test (vHIT)
- suppression head impulse paradigm
- active head impulse
- passive head impulse
- inward head impulse
- outward head impulse
- UNILATERAL VESTIBULAR LOSS
- OCULAR REFLEX
- VIDEO
- VOR
- OUTWARD