The rebound response plays a role in the motion mechanisms and perception

Abstract

9Motion estimation is an essential ability for sighted animals to survive in their natural 10 environment. Many anatomical and electrophysiological studies on low visual levels have been 11 based on the classic pioneering HRC (Hassenstein & Reichaedt Correlator) computational model. 12 The accumulated experimental findings, which have given rise to a debate in the current 13 computational models regarding the interaction between the On and Off pathways. The previous 14 algorithms were challenged to correctly predict physiological experiment results and the two types 15 of motion: a) Phi motion, also termed apparent motion. b) Reverse-phi motion that is perceived 16 when the image contrast flips during the rapid succession. We have developed a computational 17 model supported by simulations, which for the first time leads to correct predictions of the 18 behavioral motions (phi and reverse-phi), while considering separated On and Off pathways and is 19 also in agreement with the relevant electrophysiological findings. This has been achieved through 20 the well-known neuronal response: the rebound response or "Off response". We suggest that the 21 rebound response, which has not been taken into account in the previous models, is a key player in 22 the motion mechanism, and its existence requires separation between the On and the Off pathways 23 for correct motion interpretation. We furthermore suggest that the criterial reverse-phi effect is 24 only an epiphenomenon of the rebound response for the visual system. The theoretical predictions 25 are confirmed by a psychophysical experiment on human subjects. Our findings shed new light on 26 the comprehensive role of the rebound response as a parsimonious spatiotemporal detector for 27 motion and additional memory tasks, such as for stabilization and navigation. 28 29 32the external world. This information enables animals to perform tracking, navigation stabilization, 33 and etc. A knowledge of the neuronal mechanisms and the structures of the motion detectors is 34 critical to understand how an animal behaves in its complex world. 35In general, animals, from mammals to insects, are sensitive to two types of motion. These were 36 described by pioneering studies, as a common apparent or phi motion, and an illusory motion, the 37 reverse-phi illusion (Anstis 1970). Phi motion requires at least two alternating stimuli, where the 38 second stimulus, is slightly shifted spatially relative to the first stimulus. This configuration yields 39 a perception of motion in the direction of the second stimulus. In contrast, for reverse-phi motion, 40 the second stimulus is displayed with inverse contrast polarity (in addition to the shift in spatial 41 location, as for phi motion). This yields a perception of motion in the opposite direction towards 42 the first stimulus (Anstis 1970). 43 65 into two types, where the first assumes that directionality can be detected by discrete ON and OFF 66 pathways (Leonhardt et al. 2017, 2016), while the second type assumes that there must...