Sensory and integrative properties of the fast visuomotor system

快速视觉运动系统的感觉和综合特性

• 批准号: RGPIN-2016-04747
• 负责人: Corneil, Brian
• 金额: $ 2.99万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=688360
• 关键词: Sensory; integrative; properties; fast; visuomotor

Humans are largely visual animals; vision is the main sense we use to identify objects of interest in our external world. In order to execute accurate visual actions, visual information from the outside world needs to be rapidly contextualized and integrated with current body posture to generate efficient and appropriate motor commands. Previous research has shown that such contextualization and integration can be carried out remarkably quickly by a fast visuomotor system capable of initiating a movement in less than 150 ms of a visual event (e.g., such as a corrective action to catch a falling cup of water). Precise recordings of neck and limb muscle activity have provided evidence for stimulus-locked responses (SLR), which are small bursts of muscle activity well in advance of movement onset that occur time-locked ~80-100 ms after visual stimuli.Our hypothesis is that SLRs are a signature of the fast visuomotor system mediated through the superior colliculus, a key midbrain structure for orienting.******The goal of the proposed research is to better understand the fast visuomotor system by examining the SLR in upper limb muscles, as humans execute planar reaching movements. In the first of two projects, we aim to better understand the sensory properties of the SLR. To date, the SLR has been elicited by simple punctate visual stimuli presented in isolation. Here, we will investigate the SLR following the presentation of more refined visual stimuli (e.g., varying spatial frequencies, providing stimulus motion), or complex environments (e.g., presenting multiple stimuli, or varying initial position of the eyes and hand). The findings from this project will provide information about the visual processing and pathways underlying the SLR.***In the second project, we will study the integrative properties of the SLR while participants reach in different behavioural contexts. For example, the SLR will be studied when participants move away from a stimulus, abruptly cancel an upcoming action, move in an altered visual-to-motor environment, or make a decision between uncertain alternatives. Together, the results from this project will provide functional insights into how the SLR relates to ensuing behaviour, and reflects the participant's cognitive state in a variety of different tasks.***The overall objective of this proposal is to better understand the SLR from both a sensory perspective, as the results from project 1 will provide information about the extent and timing of visual processing, and a functional perspective, as the results from project 2 will clarify how the SLR relates to ensuing behaviour. One of the particularly unique aspects of the SLR is that it is available on a trial-by-trial basis in humans; accordingly, we can leverage many of the tools normally reserved for animal neurophysiology to better understand the contribution of the fast visuomotor system to human behaviour. ********

人类在很大程度上是视觉动物；视觉是我们用来识别外部世界中感兴趣的对象的主要感觉。为了执行准确的视觉动作，来自外部世界的视觉信息需要快速地与当前的身体姿势相结合，以产生有效和适当的运动命令。先前的研究已经表明，通过能够在视觉事件(例如，接住掉落的水杯的矫正动作)的少于150ms的时间内启动运动的快速视觉运动系统，可以非常迅速地执行这样的上下文和整合。颈部和四肢肌肉活动的精确记录为刺激锁定反应(SLR)提供了证据，刺激锁定反应(SLR)是在运动开始之前很久就发生的肌肉活动的小爆发，发生在视觉刺激后约80-100ms。我们的假设是，SLR是通过上丘调节的快速视觉运动系统的标志，上丘是进行定向的关键中脑结构。*本研究的目的是通过检查人类执行平面到达动作时上肢肌肉的SLR来更好地了解快速视觉运动系统。在两个项目中的第一个项目中，我们的目标是更好地了解单反的感官特性。到目前为止，单反是由孤立呈现的简单点状视觉刺激引起的。在这里，我们将研究在呈现更精细的视觉刺激(例如，变化的空间频率，提供刺激运动)或复杂环境(例如，呈现多个刺激，或改变眼睛和手的初始位置)之后的单反。这个项目的发现将提供关于单反的视觉处理和通路的信息。*在第二个项目中，我们将研究当参与者在不同的行为环境中达到时，单反的综合特性。例如，当参与者离开刺激，突然取消即将进行的动作，在视觉到运动的环境中移动，或者在不确定的替代方案中做出决定时，单反将被研究。总而言之，本项目的结果将提供对单反与后续行为的关系的功能洞察，并反映参与者在各种不同任务中的认知状态。*本提案的总体目标是从感官角度更好地理解单反，因为项目1的结果将提供有关视觉处理的范围和时间的信息，而项目2的结果将澄清单反与后续行为的关系。单反的一个特别独特的方面是，它是在人类逐个试验的基础上获得的；因此，我们可以利用许多通常为动物神经生理学保留的工具来更好地了解快速视觉运动系统对人类行为的贡献。********