Multisensory integration during self-motion perception

概述：当我们在复杂的环境中移动时，我们的大脑必须有效地整合来自视觉、肌肉和关节（本体感觉）以及内耳加速探测器（前庭）的信息。这些感觉和运动输入的最佳整合使我们能够更确定地估计运动参数，如速度，距离和方向。传统上，这些感觉系统中的每一个都是彼此独立研究的，但这项研究计划的目的是量化这些多重感觉输入在自我运动期间如何在大脑中整合。本研究计划的目标是实证地评估已建立的多感觉整合原则，并引入新的实验操作，旨在更好地表征自我运动感知过程中的视觉、本体感觉和前庭整合。具体而言，它旨在：

Overview: As we move through complex environments, our brain must effectively integrate information from vision, muscles and joints (proprioception), and the acceleration detectors in the inner ear (vestibular). An optimal integration of these sensory and motor inputs allows us to estimate movement parameters such as speed, distance, and heading direction with greater certainty. Traditionally, each of these sensory systems has been studied independently of one another, but this research program is aimed at quantifying how these multiple sensory inputs are integrated in the brain during self-motion. The objectives of the proposed research program will be to empirically evaluate established tenets of multisensory integration, as well as to introduce novel experimental manipulations aimed at better characterizing visual, proprioceptive, and vestibular integration during self-motion perception. Specifically it aims to: Objective 1: In the context of self-motion perception, identify the limits of the multisensory “binding window” (i.e. the range of spatio-temporal disparities over which multiple cues are still integrated), by measuring how the magnitude of a) spatial and b) temporal conflicts between visual and vestibular signals affect optimal cue weighting. Objective 2: Assess the effects of changing cue reliabilities (e.g. reducing the quality of dynamic visual input) on multisensory self-motion perception during either experimentally introduced a) transient reductions in individual cue reliabilities, or b) prolonged reductions in individual cue reliabilities. Objective 3: Consider the aging brain as a model for understanding how naturally-occurring, global reductions in cue reliabilities across several sensory systems (e.g. loss of visual acuity and vestibular sensitivity) affect multisensory integration strategies. Scientific Approach: This research will be conducted using a state-of-the-art, immersive, Virtual Reality lab combined with a motion platform. These facilities allow us to systematically manipulate the information provided to each sensory channel, as well as to create subtle conflicts between sensory systems. We will use well-established psychophysical paradigms during both passive self-motion tasks (i.e. heading estimation on the motion simulator) and active self-motion tasks (i.e. travelled distance estimation while walking on a treadmill). Impact: These studies will have significant, global theoretical impacts in the fields of multisensory integration. They will make particularly relevant contributions to the literatures on self-motion perception, spatial updating, locomotion, and aging. Long-term applied impacts of these studies may also be observed in fields including, locomotor rehabilitation, design of simulators, and vehicle design for an aging population.