Investigating the neuro-cognitive fundaments of the perception of illusory self-motion

自我运动的知觉是由不同感觉信息的整合所引导的，包括视觉、前庭（内耳）和本体感觉（肌肉和关节的位置）线索。这些感官传递的信息通常是一致的，从而产生对空间运动的全局、准确的感知。然而，在某些情况下，也可以体验到虚幻的自我运动或运动（即，尽管没有真实的身体运动，但自我运动感知）。向量在现实世界中的一个例子是火车错觉，坐在静止的火车上，看到旁边的火车在移动，就会产生自己的火车在移动的错觉。在模拟器或虚拟现实（VR）等刺激很大一部分视野的情况下也可以观察到向量，并且在这些应用中起着重要作用。向量的神经认知基础仍然是未知的。这项研究计划的总体目标是通过结合心理生理学和行为方法来填补这一空白。具体目标包括：(1)使用脑电图（EEG）识别在感知向量过程中皮层活动的时间和空间方面。(2)研究多感官线索（视觉、听觉、触觉）的组合如何影响向量方面的神经认知反应。(3)确定认知方面，例如上下文信息，影响向量及其在脑电图中的检测程度。该研究项目将使用多伦多康复研究所研究设施的两个沉浸式VR实验室进行：StreetLab，配备了带有地板投影和环绕声的大型弧形投影屏幕；还有立体投影实验室（StereoProLab），它可以将图像立体投影到大屏幕上，以及覆盖很大一部分视野的多屏幕阵列。这两种设备都已被证明能够可靠地产生矢量，并将允许系统地操纵感官信息。通过自我报告（向量开始、偏移、持续时间和强度）来测量向量。一个32通道的脑电图系统将在两个实验室使用，以测量在向量阶段的大脑活动。本研究将在多个层面上产生影响：(1)提高对矢量的理论认识。(2)识别与主观情绪体验相关的客观神经认知标记。(3)开发使用虚拟环境的应用程序，其中向量通常是一种理想的现象，例如在训练和康复的背景下使用VR。

The perception of self-motion is guided by the integration of different sensory information, including visual, vestibular (inner-ears), and proprioceptive (position of the muscles and joints) cues. Information delivered by these senses is typically congruent, giving rise to a global, accurate perception of movement through space. However, under certain circumstances illusory self-motion or vection (i.e., self-motion perception despite the absence of real, physical movement) can also be experienced. An example for vection in real-world situation is the train illusion, whereby sitting in a stationary train and seeing a neighboring train moving creates the illusion that one's own train is moving. Vection can also be observed in situations that stimulate a large proportion of the visual field, such as in simulators or virtual reality (VR) and plays an important role in these applications. The neuro-cognitive fundaments of vection are still unknown. The overall goal of this research program is to fill this gap by combining psychophysiological and behavioral methods. The specific objectives include: (1) Identifying the temporal and spatial aspects of cortical activity during the perception of vection using electroencephalography (EEG). (2) Investigating how the combination of multisensory cues (visual, auditory, haptic) affects the neuro-cognitive responses with respect to vection. (3) Determining the extent to which cognitive aspects, e.g. contextual information, influence vection and its detection in the EEG. This research program will be conducted using two immersive VR laboratories that are part of Toronto Rehabilitation Institute's research facilities: StreetLab, equipped with a large, curved projection screen with floor projection and surround sound; and, StereoProLab, which offers stereoscopic projection of images onto a large screen and an array of multiple screens covering a large proportion of the visual field. Both facilities have been proven to reliably generate vection and will allow to systematically manipulate sensory information. Vection will be measured through self-reports (vection onset, offset, duration, and intensity). A 32-channel EEG system will be used in both laboratories to measure brain activity during phases of vection. This research will have impact on multiple levels: (1) Improving the theoretical understanding of vection. (2) Identification of objective neuro-cognitive markers that correlate with the subjective experience of vection. (3) Development of applications that use virtual environments where vection is often a desired phenomenon, e.g. the use of VR in the context of training and rehabilitation.