The relative importance of retinal error and prediction in saccadic adaptation
The relative importance of retinal error and prediction in saccadic adaptation
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DOI：
10.1152/jn.00746.2011
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发表时间：
2012-06-01
影响因子：
2.5
通讯作者：
Wallman, Josh
中科院分区：
文献类型：
--
作者：
Collins, Therese;Wallman, Josh
柯林斯·T（Collins T）、沃尔曼·J（Wallman J.）视网膜误差和扫视适应预测的相对重要性。J Neurophysiol 107：3342-3348，2012.首次发表于2012年3月21日; doi：10.1152/jn.00746.2011.-当扫视系统地错过他们的视觉目标时，他们的幅度调整，导致位置误差逐渐减小。传统上，这种适应被视为由视网膜误差（主扫视终点和视觉目标之间的距离）驱动。最近的研究表明，眼球系统被告知眼睛的位置，因此并非所有的“视网膜错误”都是意料之外的。本研究比较了两种可能驱动扫视适应的误差信号：视网膜误差和预测误差（预测和实际扫视后图像之间的差异）。受试者在两个连续的会话中对视觉目标进行扫视。在第一个会话中，如果幅度小于（或者，在其他实验中，大于）运行中位数，则在扫视执行期间目标被熄灭，从而修改受试者在扫视期间没有移动目标的情况下经历的平均视网膜误差，如在常规适应范例中那样。在第二阶段，目标在扫视开始时熄灭，并在再现第一阶段中记录的逐个试验视网膜错误的位置重新打开。尽管第一次和第二次会议的视网膜错误是相同的，适应是几倍更大的第二次会议时，预测的目标位置已经改变。这些结果表明，眼睛知道它在哪里着陆以及它期望目标在哪里，并且与这种预测的偏差比视网膜误差更强烈地驱动扫视适应。
Collins T, Wallman J. The relative importance of retinal error and prediction in saccadic adaptation. J Neurophysiol 107: 3342-3348, 2012. First published March 21, 2012; doi:10.1152/jn.00746.2011.-When saccades systematically miss their visual target, their amplitude adjusts, causing the position errors to be progressively reduced. Conventionally, this adaptation is viewed as driven by retinal error (the distance between primary saccade endpoint and visual target). Recent work suggests that the oculomotor system is informed about where the eye lands; thus not all "retinal error" is unexpected. The present study compared two error signals that may drive saccade adaptation: retinal error and prediction error (the difference between predicted and actual postsaccadic images). Subjects made saccades to a visual target in two successive sessions. In the first session, the target was extinguished during saccade execution if the amplitude was smaller (or, in other experiments, greater) than the running median, thereby modifying the average retinal error subjects experienced without moving the target during the saccade as in conventional adaptation paradigms. In the second session, targets were extinguished at the start of saccades and turned back on at a position that reproduced the trial-by-trial retinal error recorded in the first session. Despite the retinal error in the first and second sessions having been identical, adaptation was severalfold greater in the second session, when the predicted target position had been changed. These results argue that the eye knows where it lands and where it expects the target to be, and that deviations from this prediction drive saccade adaptation more strongly than retinal error alone.