Gaze-Centered Remapping of Remembered Visual Space in an Open-Loop Pointing Task
Gaze-Centered Remapping of Remembered Visual Space in an Open-Loop Pointing Task
复制标题
开环指向任务中以凝视为中心的记忆视觉空间重新映射
作者：
D. Henriques;E. M. Klier;Michael A. Smith;Deborah Lowy;J. Crawford
建立一个连贯的内部参考框架的视觉空间表示和保持这个框架的完整性在眼球运动被认为是至关重要的知觉和运动控制。通过内部比较视网膜信号与眼睛位置，可以构建稳定的头中心表示。或者，视觉记忆轨迹可以在以眼为中心的框架内主动重新映射，以补偿每次眼睛运动。我们测试了这些模型，通过测量误差手动指向（在完全黑暗中）短暂闪烁的中央目标在三个oculabetics范式，受试者准确地指出，当目光保持在目标位置（控制范式）。然而，当稳定地注视周边位置（静态范例）时，受试者将中心目标的视网膜偏心率放大了13.4 ± 5.1%。在关键的“动态”范式中，被试先短暂地注视中心目标，然后在指向记忆中的目标位置之前向周边扫视。我们的头中心模型预测准确的指向（如在控制范式）独立的扫视，而我们的oculocentric模型预测的内部转移的视网膜轨迹的误判（如在静态范式）。事实上，指向错误显著大于控制错误（p ≤ 0.003），并且与静态范式错误无法区分（p ≥ 0.25）。不同最终注视方向的指向误差（动态与静态范例）散点图显示总体斜率为0.97，与头中心预测（0.0）相矛盾，支持眼中心预测（1.0）。改变固定和指向目标的方向证实，这些错误是一个功能的视网膜移位记忆痕迹，而不是眼睛的位置本身。为了调和这些结果与以前的指向实验，我们提出了一个“按需转换”模型的视觉控制，其中多个视觉目标被存储和旋转（noncommutative）内的oculocentric框架，而只有选择目标被进一步转化为头部或身体为中心的帧电机执行。
Establishing a coherent internal reference frame for visuospatial representation and maintaining the integrity of this frame during eye movements are thought to be crucial for both perception and motor control. A stable headcentric representation could be constructed by internally comparing retinal signals with eye position. Alternatively, visual memory traces could be actively remapped within an oculocentric frame to compensate for each eye movement. We tested these models by measuring errors in manual pointing (in complete darkness) toward briefly flashed central targets during three oculomotor paradigms; subjects pointed accurately when gaze was maintained on the target location (control paradigm). However, when steadily fixating peripheral locations (static paradigm), subjects exaggerated the retinal eccentricity of the central target by 13.4 ± 5.1%. In the key “dynamic” paradigm, subjects briefly foveated the central target and then saccaded peripherally before pointing toward the remembered location of the target. Our headcentric model predicted accurate pointing (as seen in the control paradigm) independent of the saccade, whereas our oculocentric model predicted misestimation (as seen in the static paradigm) of an internally shifted retinotopic trace. In fact, pointing errors were significantly larger than were control errors (p ≤ 0.003) and were indistinguishable (p ≥ 0.25) from the static paradigm errors. Scatter plots of pointing errors (dynamic vs static paradigm) for various final fixation directions showed an overall slope of 0.97, contradicting the headcentric prediction (0.0) and supporting the oculocentric prediction (1.0). Varying both fixation and pointing-target direction confirmed that these errors were a function of retinotopically shifted memory traces rather than eye position per se. To reconcile these results with previous pointing experiments, we propose a “conversion-on-demand” model of visuomotor control in which multiple visual targets are stored and rotated (noncommutatively) within the oculocentric frame, whereas only select targets are transformed further into head- or bodycentric frames for motor execution.
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影响因子：
4.4
作者：
Demer,JL;Miller,JM;Poukens,V;Vinters,HV;Glasgow,BJ
通讯作者：
Glasgow,BJ
在三个维度上轻松移动：唐德斯定律是否适用于手臂运动？
DOI：
10.1523/jneurosci.15-09-06271.1995
发表时间：
1995
期刊：
The Journal of neuroscience : the official journal of the Society for Neuroscience
影响因子：
--
作者：
Soechting,JF;Buneo,CA;Herrmann,U;Flanders,M
通讯作者：
Flanders,M
决定猴子眼球扫视运动幅度和方向的信号特性。
影响因子：
2.5
作者：
McKenzie,A;Lisberger,SG
通讯作者：
Lisberger,SG
扫视可以瞄准追踪过程中闪现的目标的空间位置。
影响因子：
2.5
作者：
Schlag,J;Schlag-Rey,M;Dassonville,P
通讯作者：
Dassonville,P
影响因子：
2.5
作者：
Sparks,DL;Porter,JD
通讯作者：
Porter,JD