Neural Representation of Vibrissal Self-Movement in the Thalamus

描述（由申请人提供）：我们对生物体如何通过体感感知自己的运动感兴趣。自我运动感知被认为对理解外部世界（例如，当一个人的手指在凹凸不平的表面上移动时）和对运动的在线控制（例如，当一个人闭着眼睛试图用手指触摸自己的鼻子时）都很重要。为了研究这个问题，我们使用啮齿动物的振动系统作为一个可处理的哺乳动物模型系统，因为(1)该系统的神经解剖学特征相对较好，(2)该系统相对容易进行实验操作，(3)该系统的灵敏度可与人类触摸相媲美。啮齿动物用触须来感知外部世界。通过有节奏地前后摆动它们的触须，这种行为被称为“拂动”，触须接触面部附近的物体。这种行为使动物能够形成对周围环境的感知。在根据移动传感器的输入形成这些感知时，啮齿动物必须跟踪自己的运动以及外部物体。这项提议的目的是确定：(1)在外围被“重新编码”的运动信息是如何在丘脑中被处理的（并随后传递到大脑皮层），(2)这些信息与外部物体信息结合的程度，以及(3)这种处理发生的神经机制。对自我运动感知如何参与运动控制的基本科学理解目前尚缺乏，这可能有助于我们理解导致运动控制障碍的各种神经功能障碍，如中风和瘫痪。这样的理解也可以为神经修复装置的设计提供信息，旨在恢复有这种损伤的患者的感觉和运动能力。目前，这些原型设备在没有体感反馈的情况下运行，因此患者难以控制。内在和外在感觉的整合也可能是更广泛的“自我”感的重要组成部分，它超越了感觉运动领域，被认为是人类状况的一个重要方面。

DESCRIPTION (provided by applicant): We are interested in how organisms perceive their own movements through somatosensation. Self- movement perception is thought to be important both for understanding the external world (i.e. as one passes his fingers over a bumpy surface) and for the on-line control of movement (i.e. as one tries to touch his own nose with his finger while his eyes are closed). To study this question, we use the rodent vibrissal system as a tractable mammalian model system because (1) the neuroanatomy for this system is relatively well-characterized, (2) the system is relatively easily accessible to experimental manipulation, and (3) the sensitivity of the system rivals that of human touch. Rodents use their vibrissae (whiskers) to sense the external world. By rhythmically sweeping their vibrissae back and forth in a behavior known as "whisking", the vibrissae contact objects near the face. This behavior allows the animal to form perceptions about its immediate surroundings. In forming these perceptions based on inputs from moving sensors, rodents must keep track of their own movements as well as external objects. The aims of this proposal are to determine: (1) how movement information that is "re- coded" at the periphery is processed in the thalamus (and subsequently relayed to the cortex of the brain), (2) the degree to which such information is combined with information about external objects, and (3) the neural mechanisms by which this processing occurs. A basic scientific understanding of how perception of self-movement is involved in motor control is currently lacking, and could potentially help us to understand a variety of neurological dysfunctions which result in motor control impairments, such as stroke and paralysis. Such an understanding could also inform the design of neural prosthetic devices aimed at restoring sensation and motor capabilities to patients with such impairments. Currently these prototype devices operate in the absence of somatosensory feedback are are consequently difficult for patients to control. The integration of intrinsic and extrinsic sensations may also be an important part of a broader sense of "self", which extends beyond the sensorimotor domain and is thought to be an important aspect of the human condition.