Effects of learning on smooth pursuit during transient disappearance of a visual target
Effects of learning on smooth pursuit during transient disappearance of a visual target
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DOI：
10.1152/jn.00869.2002
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发表时间：
2003-08-01
影响因子：
2.5
通讯作者：
Krauzlis, RJ
中科院分区：
文献类型：
--
作者：
Madelain, L;Krauzlis, RJ
先前的研究已经证明了追逐系统中的学习，但尚不清楚这些影响是否是视觉或运动处理变化的结果。在视觉目标短暂消失期间保持平滑追踪的能力提供了一种在没有视觉输入的情况下评估追踪特性的方法。为了研究学习对追求的非视觉信号的长期影响，我们使用了操作性条件反射程序。通过在准确跟踪期间提供强化听觉刺激，我们将目标消隐期间的追踪速度增益从基线训练中的 0.59 增加到 8 到 10 次每日训练后的 0.89。学习也减少了眼跳的发生。学习到的效果可推广到未经训练的目标速度，并在有纹理的视觉背景下持续存在。在轭对照组中，强化物与受试者的反应无关，并且速度增益保持不变（训练前后分别从 0.6 到 0.63）。在没有接受强化的对照组中，重复任务后增益略有增加（训练前后分别从 0.63 增加到 0.71）。使用追踪模型，我们表明可以通过修改视网膜外信号的增益来模拟这些学习效果。我们的结果表明，习得的偶然事件可以在没有视觉信号的情况下提高眼动速度，并支持这样的观点：追逐是由可以经历长期可塑性的视网膜外信号调节的。
Previous research has demonstrated learning in the pursuit system, but it is unclear whether these effects are the result of changes in visual or motor processing. The ability to maintain smooth pursuit during the transient disappearance of a visual target provides a way to assess pursuit properties in the absence of visual inputs. To study the long-term effects of learning on nonvisual signals for pursuit, we used an operant conditioning procedure. By providing a reinforcing auditory stimulus during periods of accurate tracking, we increased the pursuit velocity gain during target blanking from 0.59 in the baseline session to 0.89 after 8 to 10 daily sessions of training. Learning also reduced the occurrence of saccades. The learned effects generalized to untrained target velocities and persisted in the presence of a textured visual background. In a yoked-control group, the reinforcer was independent of the subjects' responses, and the velocity gain remained unchanged (from 0.6 to 0.63, respectively, before and after training). In a control group that received no reinforcer, gain increased slightly after repetition of the task (from 0.63 to 0.71, respectively, before and after training). Using a model of pursuit, we show that these effects of learning can be simulated by modifying the gain of an extra-retinal signal. Our results demonstrate that learned contingencies can increase eye velocity in the absence of visual signals and support the view that pursuit is regulated by extra-retinal signals that can undergo long-term plasticity.