VESTIBULAR INFLUENCES ON SPATIAL ORIENTATION AND VISUOSPATIAL CONSTANCY

前庭对空间定向和视觉空间稳定性的影响

• 批准号: 8252506
• 负责人: Dora Angelaki
• 金额: $ 39.13万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2016-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8252506
• 关键词: Address; Alzheimer' s Disease; Behavioral; Brain; Calibration; Clinical; Cognitive deficits; Conflict (Psychology); Cues; Discrimination; Disease; Disorientation; Ensure; Environment; Feedback; Foundations; Freedom; Functional disorder; Grant; Head; Head Movements; Human; Image; Impairment; Knowledge; Macaca; Macaca mulatta; Mediating; Methodology; Modality; Modeling; Monkeys; Motion; Motion Perception; Neurologic; Patients; Pattern; Perception; Performance; Probability Theory; Process; Property; Psychophysics; Retina; Rewards; Scheme; Sensory; Signal Transduction; Space Perception; Specific qualifier value; Stimulus; System; Testing; Therapeutic; Time; Vision; Visual; Visual Motion; Visual Perception; Visuospatial; Weight; Work; base; human subject; multisensory; object motion; optic flow; otoconia; relating to nervous system; research study; segregation; sensor; sensory system; spatial vision; vestibulo-ocular reflex; visual-vestibular

DESCRIPTION (provided by applicant): The pattern of image motion across the retina (optic flow) during self-motion provides a powerful cue to the heading direction of the observer. However, optic flow processing poses a number of computationally difficult problems, the most notable example being segregation of object motion from self-motion. Vestibular signals about the linear components of head movement can greatly simplify the extraction of behaviorally relevant information from optic flow. Using quantitative human psychophysics, here we test the hypothesis that vestibular information can be used by the brain to solve the flow parsing problem and distinguish object motion and self-motion. In addition, we explore whether visual and vestibular signals maintain internal calibration such as to ensure that estimates of the same stimulus by different sensors agree with one another. By exposing subjects to spatially conflicting optic flow and vestibular heading information, we test two models of internal consistency: a visual dominance model, which expects that, like the vestibulo-ocular reflex, vestibular perception always changes to become consistent with vision, and a reliability-based calibration model, which depends on cue reliability and assures minimum variance sensory estimates over time. According to the latter, vestibular perception should adapt towards the visually-specified heading when visual reliability is higher than the vestibular reliability and visual perception should adapt towards the vestibular-specified heading when visual reliability is lower than the vestibular reliability. We will also examine the effects of external feedback and how subjects weigh internal consistency versus external accuracy. A 6-degree-of-freedom motion platform with attached large field-of-view stereo projection system and two-alternative-forced-choice methodology will be used for all experiments. Findings are important for understanding basic perceptual visual/vestibular interactions using quantitative methodology and opening new directions in the fields of basic and clinical spatial orientation psychophysics. PUBLIC HEALTH RELEVANCE: Understanding multisensory integration and self-motion perception would promote new strategies for treating spatial disorientation deficits common to many brain dysfunctions, including Alzheimer's disease. One of these deficits is an impaired ability to judge heading from optic flow, and this impairment is correlated with patients' difficulty in navigating through their surroundings. Better localization of these functions would help targeting new Alzheimer's therapies. In addition, neurological correlates of otolith disorders are still a mystery, posing a major hurdle in defining effective therapeutic strategies. Understanding the properties of otolith-mediated self- motion perception are important for understanding and treating basic postural and spatial orientation deficits. Our experiments aim at filling a very notable gap in knowledge, important for understanding and ultimately treating basic and cognitive deficits of spatial perception.

描述（由申请人提供）：在自我运动过程中，图像在视网膜上的运动模式（光流）为观察者的前进方向提供了强有力的线索。然而，光流处理带来了许多计算难题，最显著的例子是物体运动与自运动的分离。关于头部运动线性分量的前庭信号可以大大简化从光流中提取行为相关信息的过程。本文运用定量的人类心理物理学，对前庭信息可以被大脑用来解决流解析问题和区分物体运动和自我运动的假设进行了验证。此外，我们还探讨了视觉和前庭信号是否保持内部校准，以确保不同传感器对同一刺激的估计彼此一致。通过将受试者暴露在空间冲突的光流和前庭头部信息中，我们测试了两种内部一致性模型：一种是视觉优势模型，它期望前庭感知与视觉一致，就像前庭-眼反射一样，前庭感知总是会发生变化，从而与视觉一致；另一种是基于可靠性的校准模型，它依赖于线索可靠性，并确保随着时间的推移，感官估计的方差最小。根据前庭信度理论，当视觉信度高于前庭信度时，前庭知觉应适应视觉指定的航向；当视觉信度低于前庭信度时，视觉知觉应适应前庭指定的航向。我们还将研究外部反馈的影响，以及受试者如何权衡内部一致性与外部准确性。所有实验将使用一个带有大视场立体投影系统的6自由度运动平台和双选项强迫选择方法。这些发现对于运用定量方法理解基本的感知视觉/前庭相互作用具有重要意义，并为基础和临床空间取向心理物理学领域开辟了新的方向。