Author:
Park Joo Hyun,Cho Sung Ik,Choi June,Han JungHyun,Rah Yoon Chan
Abstract
AbstractThis study assessed the pupil responses in the sensory integration of various directional optic flows during the perception of gravitational vertical. A total of 30 healthy participants were enrolled with normal responses to conventional subjective visual vertical (SVV) which was determined by measuring the difference (error angles) between the luminous line adjusted by the participants and the true vertical. SVV was performed under various types of rotational (5°/s, 10°/s, and 50°/s) and straight (5°/s and 10°/s) optic flows presented via a head-mounted display. Error angles (°) of the SVV and changes in pupil diameters (mm) were measured to evaluate the changes in the visually assessed subjective verticality and related cognitive demands. Significantly larger error angles were measured under rotational optic flows than under straight flows (p < 0.001). The error angles also significantly increased as the velocity of the rotational optic flow increased. The pupil diameter increased after starting the test, demonstrating the largest diameter during the final fine-tuning around the vertical. Significantly larger pupil changes were identified under rotational flows than in straight flows. Pupil changes were significantly correlated with error angles and the visual analog scale representing subjective difficulties during each test. These results suggest increased pupil changes for integrating more challenging visual sensory inputs in the process of gravity perception.
Funder
National Research Foundation of Korea (NRF) funded by the Ministry of Education
Publisher
Springer Science and Business Media LLC
Reference55 articles.
1. Cullen, K. E. & Taube, J. S. Our sense of direction: Progress, controversies and challenges. Nat. Neurosci. 20, 1465–1473 (2017).
2. De Vrijer, M., Medendorp, W. P. & Van Gisbergen, J. A. Shared computational mechanism for tilt compensation accounts for biased verticality percepts in motion and pattern vision. J. Neurophysiol. 99, 915–930 (2008).
3. MacNeilage, P. R., Banks, M. S., Berger, D. R. & Bülthoff, H. H. A Bayesian model of the disambiguation of gravitoinertial force by visual cues. Exp. Brain Res. 179, 263–290 (2007).
4. Gibb, R. W. Visual spatial disorientation: Revisiting the black hole illusion. Aviat. Space Environ. Med. 78, 801–808 (2007).
5. Meeks, R. K., Anderson, J. & Bell, P. M. Physiology of spatial orienttion. in StatPearls (StatPearls Publishing, Treasure
Island (FL), 2021).