TY - GEN A1 - Knorr, Alexander G. A1 - Gravot, Céline M. A1 - Gordy, Clayton A1 - Glasauer, Stefan A1 - Straka, Hans T1 - I spy with my little eye: a simple behavioral assay to test color sensitivity on digital displays T2 - Biology Open Y1 - 2018 U6 - https://doi.org/10.1242/bio.035725 SN - 2046-6390 VL - 7 IS - 10 ER - TY - GEN A1 - Lehnen, Nadine A1 - Kellerer, Silvy A1 - Knorr, Alexander G. A1 - Schlick, Cornelia A1 - Jahn, Klaus A1 - Schneider, Erich A1 - Heuberger, Maria A1 - Ramaioli, Cecilia T1 - Head-Movement-Emphasized Rehabilitation in Bilateral Vestibulopathy T2 - Frontiers in Neurology Y1 - 2018 U6 - https://doi.org/10.3389/fneur.2018.00562 SN - 1664-2295 VL - 9 ER - TY - GEN A1 - Knorr, Alexander G. A1 - Gravot, Céline M. A1 - Glasauer, Stefan A1 - Straka, Hans T1 - Image motion with color contrast suffices to elicit an optokinetic reflex in Xenopus laevis tadpoles T2 - Scientific Reports N2 - The optokinetic reflex is a closed-loop gaze-stabilizing ocular motor reaction that minimizes residual retinal image slip during vestibulo-ocular reflexes. In experimental isolation, the reflex is usually activated by motion of an achromatic large-field visual background with strong influence of radiance contrast on visual motion estimation and behavioral performance. The presence of color in natural environments, however, suggests that chromatic cues of visual scenes provide additional parameters for image motion detection. Here, we employed Xenopus laevis tadpoles to study the influence of color cues on the performance of the optokinetic reflex and multi-unit optic nerve discharge during motion of a large-field visual scene. Even though the amplitude of the optokinetic reflex decreases with smaller radiance contrast, considerable residual eye movements persist at the ‘point of equiluminance’ of the colored stimuli. Given the color motion preferences of individual optic nerve fibers, the underlying computation potentially originates in retinal circuits. Differential retinal ganglion cell projections and associated ocular motor signal transformation might further reinforce the color dependency in conceptual correspondence with head/body optomotor signaling. Optokinetic reflex performance under natural light conditions is accordingly influenced by radiance contrast as well as by the color composition of the moving visual scene. Y1 - 2021 U6 - https://doi.org/10.1038/s41598-021-87835-2 SN - 2045-2322 VL - 11 ER - TY - CHAP A1 - Glasauer, Stefan A1 - Knorr, Alexander G. ED - Fritzsch, Bernd ED - Straka, Hans T1 - Physical Nature of Vestibular Stimuli T2 - The Senses: A Comprehensive Reference, Volume 6: Vestibular System and Balance N2 - The vestibular sensors in the inner ear measure head movement with respect to an inertial frame of reference. The chapter describes the principles of measurement of the vestibular sensors, the physical stimuli that are measured, and specific issues that require central processing. An overview about so-called artificial vestibular stimuli that mimic the effect of natural head movement is provided. Y1 - 2020 U6 - https://doi.org/10.1016/B978-0-12-809324-5.23909-6 SP - 6 EP - 11 PB - Elsevier CY - Amsterdam ET - 2. Edition ER -