Augmented error feedback for control of saccade timing and amplitude

描述（由申请人提供）：人类具有非凡的预测运动能力，以克服神经处理的延迟，并适应因衰老和疾病而引起的变化。在每种情况下，正常的功能都依赖于对感官错误信息的检测和处理，以便正确地规划未来的行为。我们提出了一种新的误差反馈方法，以提高预测和自适应能力。当看到节奏约为1hz的周期性视觉目标时，正常受试者自然会做出预测性扫视——它们在给定目标的视觉反馈之前被触发，延迟时间为-100至+100毫秒。预测扫视的序列是相关的：过去扫视的表现被存储，并在后续扫视的时间考虑。小脑功能缺陷患者的初步证据表明，他们在进行这些预测性运动方面存在缺陷，这至少部分是由于缺乏对先前运动错误的监测、存储和处理。这项研究计划的最终目标是以新的方式向这些患者提供扫视错误信息，以帮助他们提高预测扫视的时间和准确性。我们的方法是用听觉信息或不同形式的视觉信息来增加每次扫视的正常视觉误差，并进一步呈现在以前几次试验中积累的错误信息，而不仅仅是最近的错误信息。这项研究计划有四个目标。首先，确定增广反馈对预测扫视时间控制的有效性。我们将在每次试验中为受试者提供时序误差的增强听觉反馈，以将时序误差驱动到所需值并减少其可变性。这种反馈以蜂鸣声的形式出现，当眼跳发生或其时间落在期望的范围内时产生。第二，增加连续预测扫视之间的相关性。这些相关性在正常受试者中自然发生，并反映了先前的表现被用来编程后续动作的事实。我们将确定这些相关性是否具有性能优势，并尝试通过提供基于前几次扫视而不是前一次扫视累积的时间误差的错误反馈来增加其程度。第三，利用位置误差的误差反馈，采用类似的方法控制预测扫视的端点（振幅）。第四，使用类似的方法来提高对双步刺激的适应能力：当眼睛靠近一个视觉目标时，它会移动，经过一段时间的适应后，当初始位置出现一个目标时，眼睛会扫视到位移的目标位置。通过提供基于位移目标位置的增强反馈，我们希望提高这种适应的速度和程度。所有程序将在正常人和预测和适应缺陷的小脑患者中进行。该方法在运动学习中具有最终用途，因此最终目的是提高小脑患者的适应能力，这对康复计划具有深远的影响。

DESCRIPTION (provided by applicant): Humans have a remarkable ability to make predictive movements in order to overcome delays in neural processing, and to adapt to changes due to aging and disease. In each case, proper functioning relies on the detection and processing of sensory error information in order to properly program future behavior. We propose a new approach to presenting error feedback, to improve prediction and adaptation. When presented with periodically paced visual targets paced at about 1 Hz, normal subjects naturally make predictive saccades - they are triggered before visual feedback from a given target, with latencies of -100 to +100 msec. Sequences of predictive saccades are correlated: performance of past saccades is stored and taken into account in the timing of subsequent saccades. Initial evidence in patients with cerebellar deficits is that they have deficiencies in making these predictive movements, and that this is due at least in part to deficiencies in monitoring, storing, and processing the errors of previous movements. The ultimate goal of this research program is to present saccade error information to these patients in new ways, to help them improve predictive-saccade timing and accuracy. Our approach is to augment the normal visual error from each saccade with auditory information or with visual information in a different form, and further to present error information that has been accumulated over several previous trials rather than just the most recent. The research plan has four aims. First, determine the effectiveness of augmented feedback for control of predictive-saccade timing. We will supply augmented auditory feedback of timing error to the subject on each trial, to drive timing error to a desired value and to decrease its variability. This feedback is in the form of a beep generated when a saccade is generated or when its timing falls within a desired range. Second, increase correlations between consecutive predictive saccades. These correlations occur naturally in normal subjects, and reflect the fact that previous performance is used to program subsequent movements. We will determine if there is a performance advantage to these correlations, and attempt to increase their extent by providing error feedback based on timing error accumulated over several previous saccades rather than the single preceding one. Third, use similar methods to control endpoints (amplitudes) of predictive saccades, using error feedback of position errors. Fourth, use similar methods to improve the ability to adapt to a double-step stimulus: a visual target moves as the eyes approach it, and after a period of adaptation the eyes make a saccade to the displaced target position when presented with a target at the initial location. By providing augmented feedback based on displaced target position, we hope to improve the rate and extent of this adaptation. All procedures will be performed on normals and cerebellar patients with deficits in prediction and adaptation. The methodology has its ultimate usefulness in motor learning, thus the final aim has the goal of improving adaptive capabilities of cerebellar patients, which can have profound impact on rehabilitation programs. PUBLIC HEALTH RELEVANCE: Impaired ability to make predictive movements, and to adaptive to changing conditions, can seriously impact health - especially if these largely automatic processes then require conscious processing. Impaired prediction adversely affects the ability to generate appropriate motor actions in anticipation of upcoming requirements, and impaired adaptation affects that ability to adjust for changes due to aging and disease. Procedures that train the brain to compensate for deficiencies in these areas can be of great benefit in programs of neural rehabilitation.