The Effect of Different Head Movement Paradigms on Vestibulo-Ocular Reflex Gain and Saccadic Eye Responses in the Suppression Head Impulse Test in Healthy Adult Volunteers

Dmitrii Starkov; Bernd Vermorken; T S Van Dooren; Lisa Van Stiphout; Miranda Janssen; Maksim Pleshkov; Nils Guinand; Angelica Pérez Fornos; Vincent Van Rompaey; Herman Kingma; Raymond Van de Berg

doi:10.3389/fneur.2021.729081

The Effect of Different Head Movement Paradigms on Vestibulo-Ocular Reflex Gain and Saccadic Eye Responses in the Suppression Head Impulse Test in Healthy Adult Volunteers

Front Neurol. 2021 Sep 22:12:729081. doi: 10.3389/fneur.2021.729081. eCollection 2021.

Authors

Dmitrii Starkov^{1

2}, Bernd Vermorken¹, T S Van Dooren¹, Lisa Van Stiphout¹, Miranda Janssen^{1

3}, Maksim Pleshkov^{1

2}, Nils Guinand^{1

4}, Angelica Pérez Fornos⁴, Vincent Van Rompaey^{5

6}, Herman Kingma^{1

2}, Raymond Van de Berg^{1

2}

Affiliations

¹ Division of Balance Disorders, Department of Otorhinolaryngology and Head and Neck Surgery, Maastricht University Medical Center, Maastricht, Netherlands.
² Faculty of Physics, Tomsk State Research University, Tomsk, Russia.
³ Department of Methodology and Statistics, Care and Public Health Research Institute (CAPHRI), Maastricht University, Maastricht, Netherlands.
⁴ Service of Otorhinolaryngology Head and Neck Surgery, Department of Clinical Neurosciences, Geneva University Hospitals, Geneva, Switzerland.
⁵ Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.
⁶ Department of Otorhinolaryngology and Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium.

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. 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. 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). 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.

Keywords: active head impulse; inward head impulse; outward head impulse; passive head impulse; suppression head impulse paradigm; vestibular ocular reflex; video head impulse test (vHIT).