A neuronal process of the error signal that drives saccade adaptation

描述（由申请人提供）：运动适应是与中风、损伤或衰老引起的神经损伤相关的运动缺陷后功能恢复的重要因素。这样的电机恢复或适应由误差信号指示，该误差信号由下式计算： 大脑从期望的运动和实际产生的运动之间的不匹配。然而，处理特定错误信号的大脑回路并不清楚。我研究的长期目标是确定处理错误信号以优化感觉运动行为的神经机制。了解这些机制及其背后的电路将有助于设计运动缺陷的康复治疗。 我们已经通过使用猴子扫视眼球运动接近了我们的目标，这提供了一个理想的模型，因为扫视是精确的，只使用几块肌肉，相关的脑干神经回路已经被很好地记录下来，并且它们可以通过完善的行为范例进行运动适应。到目前为止，我们知道，复杂的尖峰放电在眼蚓部（OMV）编码运动错误和OMV是需要适应的目标扫视。OMV中的复杂尖峰起源于接受来自上级丘（SC）的投射的下橄榄的一部分。以前，我们已经表明，电微刺激的SC，定时模仿视觉错误信号，诱导眼跳适应。因此，SC似乎是错误信号通路的重要组成部分。 在这项研究中，我们提出了三个项目来测试参与编码的错误信号扫视适应的SC。第一个项目是针对确定SC是否需要适应目标扫视。我们将可逆性SC，在此期间，我们预测，猴子将无法适应其扫视时，受到行为适应范式。第二个项目是针对识别相关的SC视觉活动与视觉错误信号，驱动适应。我们将寻找SC视觉活动与错误大小（小错误比大错误更好地驱动适应）和适应率的相关性，随着适应的进展而降低。第三个项目将确定SC是否也用于适应其他类型的眼跳，包括记忆引导，延迟，扫描和表达。我们将电刺激SC后，这些不同的类型之一，以模仿错误 发信号并确定对于目标扫视，该人为误差是否引起适应。如果是，我们将测试适应是否转移到其他类型。我们预计，这三个项目的结果将有助于建立一个以前未被怀疑的作用SC眼跳适应。

DESCRIPTION (provided by applicant): Motor adaptation is an important factor in the recovery of function following motor deficits associated with neural damage due to stroke, injury or aging. Such motor recovery or adaptation, is instructed by an error signal that is calculated by the brain from the mismatch between the desired movement and the actual movement produced. However, the brain circuits that process specific error signal(s) are not understood. The long-term goal of my research is to identify the neural mechanisms that process error signals to optimize sensory-motor behavior. Understanding these mechanisms and the circuitry underlying them will assist in devising rehabilitation therapies for motor deficits. We have approached our goal by using monkey saccadic eye movements, which provide an ideal model because saccades are precise, use only a few muscles, the associated brainstem neural circuit has been well documented and they can be made to undergo motor adaptation by means of well-established behavioral paradigms. Thus far, we know that complex spike firing in the oculomotor vermis (OMV) encodes motor error and that the OMV is required for adaptation of targeting saccades. Complex spikes in the OMV originate in a part of the inferior olive that receives a projection from the superior colliculus (SC). Previously, we have shown that electrical micro-stimulation of the SC, timed to mimic visual error signals, induces saccade adaptation. Thus, the SC appears to be an important part of the error signal pathway. In this study, we propose three projects to test the involvement of the SC in coding an error signal for saccade adaptation. The first project is directed at determining whether the SC is required for adaptation of targeting saccades. We will inactivate the SC reversibly during which time we predict that the monkey will be unable to adapt its saccades when subjected to a behavioral adaptation paradigm. The second project is directed at identifying correlates in SC visual activity with the visual error signal that drives adaptation. We will look for correlations of SC visual activity wit error size (small errors drive adaptation better than large ones) and with adaptation rate, which decreases as adaptation progresses. The third project will determine whether the SC is also used for adaptation of other types of saccade, including memory-guided, delayed, scanning and express. We will electrically stimulate the SC after one of these different types to mimic an error signal and determine whether, as for targeting saccades, this artificial error causes adaptation. I it does, we will test whether the adaptation transfers to the other types. We anticipate that together the results of these three projects will help establish a previously unsuspected role for the SC in saccade adaptation.