Sensorimotor representation of the body multisensory integration and sense of self

身体多感觉统合和自我意识的感觉运动表征

• 批准号: BB/D009529/1
• 负责人: Patrick Haggard
• 金额: $ 37.66万
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FD009529%2F1
• 关键词: Sensorimotor; representation; body; multisensory; integration

The concept of self, something referred to by 'I', is central to psychology, but hard to study scientifically. The basis of self must be the body. The body is represented in the brain differently from external objects. First, I can directly move and control my body, but not other objects. Also, bodily sensory events feel different from perceptions of external objects. We ask how the bodily self relates to one's own actions and sensations, and how the brain's representation of the body modifies action and sensation processing? To do this, we need an experimental method that allows us to control whether an event is experienced as linked to my own body or not. We showed that 'Rubber Hand Illusions' (RHI) do precisely this. Subjects watch a rubber hand being touched while feeling a similar, synchronous touch on their own unseen hand. Perceptual regularity of the visual and tactile stimuli induces the illusion that the rubber hand is part of one's self: subjects incorporate the rubber hand into the mental representation of their own body. The effect is measured objectively as a drift in the perceived position of one's own hand towards the rubber hand. Results are compared to control conditions with identical visual and tactile stimuli are, but separated by a time delay between them. This asynchrony abolishes RHI. The project has 3 phases. We first compare sensory and motor aspects of sense of self using RHI. Sensory-RHI is induced by visual-tactile stimulation as above. Motor-RHI is induced by repeatedly making a simple finger movement which is repeated synchronously or asynchronously by the rubber hand, using an invisible motor. Sensory-RHI induces the feeling of 'ownership': that an external object is part of one's body. Motor-RHI induces a feeling of 'agency': that one can control the rubber hand directly by one's own command. By comparing the drift in the perceived position of one's hand towards the rubber hand, we can assess whether sensory or motor regularity makes a stronger contribution to the sense of bodily self. Is the self primarily sensory or motor? We next repeat the study in an fMRI brain scanner, and investigate which brain areas differ between synchronous and asynchronous conditions. This reveals brain regions responsible for sensory and motor aspects of self. We also look for areas of common overlap, which may integrate these aspects. The second and third phases of the project investigate which of the sensory and motor aspects of self is most fundamental. Is each aspect sufficiently powerful to influence the other? In phase 2, we assess whether the sensory self can influence motor systems. We induce sensory-RHI and then study whether a finger movement of the rubber hand (via the invisible motor) automatically activates the motor areas in the subject's brain, as if subjects were imitating or entrained by the movement that they see. A brain imaging study investigates the brain processes whereby ownership of the rubber hand can influence motor areas of the brain. In phase 3, we study the inverse relation, between motor-RHI and the sensory experience of the body. Motor-RHI is induced by voluntary movements, with synchronous or asynchronous movements of a video-projected hand. We measure the sense of touch in the hand with or without vision of a corresponding stimulus touching the video hand. Viewing touch should enhance tactile perception, and most strongly when the subject feels that the viewed hand is their own. We thus clarify whether sense of control also imparts a sense of ownership, and use fMRI to study the basis of this link in the brain. The project therefore provides an experimental and scientific way of studying aspects of the mind which are crucial to mental life, but have previously been inaccessible to science. The project links this key sense of self to specific brain processes, and to clearly-described experiences of sensation and action.

自我的概念，即“我”所指的东西，是心理学的核心，但很难科学地研究。自我的基础必须是身体。身体在大脑中的表现与外部物体不同。首先，我可以直接移动和控制我的身体，但不能控制其他物体。此外，身体感觉事件与对外部物体的感知不同。我们要问的是，身体自我如何与自己的动作和感觉相关联，大脑对身体的表征如何改变动作和感觉的处理过程？要做到这一点，我们需要一种实验方法，使我们能够控制一个事件是否与我自己的身体有关。我们证明了“橡胶手错觉”（RHI）正是这样做的。受试者观看被触摸的橡胶手，同时感觉到他们自己看不见的手上类似的同步触摸。视觉和触觉刺激的知觉规律性会导致橡胶手是自我的一部分的错觉：受试者将橡胶手纳入自己身体的心理表征中。这种效果被客观地测量为一个人自己的手朝向橡胶手的感知位置的漂移。结果进行比较，控制条件相同的视觉和触觉刺激，但它们之间的时间延迟分开。这一次，RHI被废除了。该项目有三个阶段。我们首先使用RHI比较自我感觉的感觉和运动方面。如上所述，感觉-RHI由视觉-触觉刺激诱导。电机RHI是通过重复进行一个简单的手指运动，这是同步或异步重复的橡胶手，使用一个无形的电机。感觉-RHI引起“所有权”的感觉：外部物体是身体的一部分。Motor-RHI让人产生一种“能动性”的感觉：一个人可以通过自己的命令直接控制橡胶手。通过比较一个人的手朝向橡胶手的感知位置的漂移，我们可以评估感觉或运动规律性是否对身体自我感做出更大的贡献。自我主要是感觉还是运动？接下来，我们在功能磁共振成像大脑扫描仪上重复这项研究，并调查同步和异步条件下哪些大脑区域不同。这揭示了负责自我感觉和运动方面的大脑区域。我们还寻找共同重叠的领域，这可能会整合这些方面。该项目的第二和第三阶段调查自我的感觉和运动方面是最基本的。每一个方面都有足够的力量来影响另一个方面吗？在第二阶段，我们评估感觉自我是否可以影响运动系统。我们诱导感觉RHI，然后研究橡胶手的手指运动（通过看不见的马达）是否会自动激活受试者大脑中的运动区域，就好像受试者正在模仿或被他们看到的运动所吸引。一项大脑成像研究调查了拥有橡胶手可以影响大脑运动区域的大脑过程。在第三阶段，我们研究了运动RHI和身体感觉体验之间的反比关系。运动-RHI由自愿运动引起，具有视频投影手的同步或异步运动。我们测量的触觉在手中有或没有相应的刺激触摸视频手的视觉。观看触摸应该增强触觉感知，并且当受试者感觉到所观看的手是他们自己的手时最强烈。因此，我们澄清了控制感是否也赋予了所有权感，并使用功能磁共振成像来研究大脑中这种联系的基础。因此，该项目提供了一种实验和科学的方法来研究对心理生活至关重要的心理方面，但以前科学无法获得。该项目将这种关键的自我意识与特定的大脑过程联系起来，并与清晰描述的感觉和行动体验联系起来。