ROLE OF THE SACCADIC EYE-MOVEMENT COROLLARY DISCHARGE IN STABLE VISUAL PERCEPTION

项目摘要尽管频繁的眼跳运动扰乱了视觉输入，但仍保持了稳定的视觉感知。这种补偿的一个假设是，即将到来的眼跳的高级知识是由运动指令的内部副本--必然放电(CD)信号--提供的。这个副本被用来区分自我产生的感觉和环境干扰，并反映了原始运动命令的属性。然而，这些镜像特征在确定干扰的来源及其对视觉感知的影响方面所施加的影响目前尚不清楚。这项应用的研究目的是确定CD变异性对视觉场景中跨眼跳变化做出准确知觉判断的能力的后果，并确定CD传递的缺陷是神经系统疾病视觉知觉障碍的基础。本研究的中心假设是：(1)不同幅度和方向的眼跳运动的CD反映了原始运动指令的性质；(2)CD传输中断的患者，如精神分裂症患者，对跨眼跳视觉场景变化的感知能力会降低。这项研究利用人类心理物理学和已知的眼跳眼动系统的神经解剖学，剖析了大脑如何不断地将由我们自己的行动产生的不断变化的感觉信息合并到稳定的视觉感知中。应用的假设是建立在强大的初步数据的基础上的，这些数据表明，在正常人中利用CD来检测跨眼跳视觉场景变化的能力随着CD信号中的方差的增加而减弱，并且还受从CD和运动命令的来源预测的眼跳运动的方向的影响。这项研究的长期目标是了解必然放电在视觉感知和运动控制中的作用，目的是帮助诊断和治疗由CD传输缺陷引起的疾病。这项研究的预期结果是提供证据，证明跨眼跳变化的知觉判断受到CD信号中反映的变异性的影响，并且当CD信号在精神分裂症中的传输能力下降时，这种检测能力就会减弱。这一贡献意义重大，因为除了诊断之外，大脑中大多数不代表感觉或运动信息的内部信号目前都无法获得，而且很可能是损害高级认知功能的疾病影响了这些回路，就像精神分裂症一样。CD是少数几个可以通过实验获得的内部信号之一，通过对它的研究，可以加强对这些信号及其传输的了解。

PROJECT SUMMARY Stable visual perception is maintained despite the frequent saccadic eye-movements that disrupt the visual input. One hypothesis for this compensation is that advanced knowledge of the impending saccade is provided by an internal copy, a corollary discharge (CD) signal, of the motor command. This copy is utilized to distinguish self-generated sensations from environmental disturbances and reflects properties of the original motor command. However, the influence these mirrored characteristics exert in determining the source of a disturbance and its impact on visual perception is currently unknown. The research objective of this application is to determine the consequences of CD variability on the ability to make accurate perceptual judgments of trans-saccadic changes in the visual scene, and establish that defects in CD transmission underlie the visual perceptual disorders in neurological disease. The central hypothesis of this research is that (1) the CD of saccadic eye-movements of different amplitudes and directions reflect the properties of the original motor command and (2) patients with CD transmission disruption, such as in Schizophrenia, will demonstrate a reduced ability to perceive trans-saccadic visual scene variations. The research uses human psychophysics and the known neuroanatomy of the saccadic eye-movement system to dissect the way the brain continuously incorporates the changing sensory information that results from our own actions into a stable visual percept. The hypothesis of the application has been formulated on the basis of strong preliminary data that show the ability to utilize CD to detect trans-saccadic visual scene alterations in normal human subjects weakens with increasing variance in the CD signal and is also influenced by the direction of the saccadic eye-movement, as predicted from the source of the CD and motor command. The long-term goal of the research is to understand the role of corollary discharge in visual perception and movement control with the objective of contributing to the diagnosis and treatment of diseases that result from CD transmission deficits. The expected outcomes of the research is to provide evidence that perceptual judgments.; of trans-saccadic changes is influenced by the variability reflected in the CD signal, and that this detection ability is diminished when CD transmission is degraded in Schizophrenia. This contribution is significant because in addition to diagnostics, the majority of the internal signals in the brain that do not represent sensory or motor information are presently inaccessible, and it is likely that diseases that impair higher cognitive function affect these circuits, as in Schizophrenia. CD is one of the few internal signals that is experimentally accessible and, through its study, an enhanced understanding of these signals and their transmission can be achieved.