Motion Integration for Ocular Pursuit Does Not Hinder Perceptual Segregation of Moving Objects
Motion Integration for Ocular Pursuit Does Not Hinder Perceptual Segregation of Moving Objects
复制标题
视觉追踪的运动整合不会妨碍运动物体的感知分离
DOI：
10.1523/jneurosci.4867-13.2014
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发表时间：
2014-04-23
影响因子：
5.3
通讯作者：
Heinen, Stephen J.
中科院分区：
文献类型：
--
作者：
Jin, Zhenlan;Watamaniuk, Scott N. J.;Heinen, Stephen J.
当面对复杂的运动刺激时，大脑可以整合局部元素速度以获得单个运动信号，或者分离元素以保持对其身份的意识。整合的运动信号可以驱动平滑追踪的眼球运动（Heinen和Watamaniuk，1998），而分离的信号则引导多对象跟踪任务中对单个元素的专注跟踪（MOT; Pylyshyn和Storm，1988）。很明显，这些过程可以同时发生，因为我们可以毫不费力地追踪行走的生物，同时检查不相交的运动特征，如手臂和腿，但其潜在机制尚不清楚。在这里，我们提供的证据表明，单独的神经回路执行数学上相反的操作的整合和隔离，通过证明与双任务范式，这两个过程不共享注意力资源。人类观察者专注地跟踪组成小MOT刺激的目标元素的子集，同时在计算机显示器上翻译时用眼睛追踪它。多点刺激的整合产生了最佳追求。重要的是，在追求刺激的同时进行MOT，与单独进行每项任务相比，并没有降低任何一项任务的表现，这表明他们没有分享注意力。一个对照实验表明，追求并不驱动的整合，只有非目标，留下的MOT目标免费隔离。也没有一个预测性的策略来追求刺激，因为它的全球速度的突然变化被准确地跟踪。结果表明，不同的神经机制可以同时分离和整合相同的运动信号。
When confronted with a complex moving stimulus, the brain can integrate local element velocities to obtain a single motion signal, or segregate the elements to maintain awareness of their identities. The integrated motion signal can drive smooth-pursuit eye movements (Heinen and Watamaniuk, 1998), whereas the segregated signal guides attentive tracking of individual elements in multiple-object tracking tasks (MOT; Pylyshyn and Storm, 1988). It is evident that these processes can occur simultaneously, because we can effortlessly pursue ambulating creatures while inspecting disjoint moving features, such as arms and legs, but the underlying mechanism is unknown. Here, we provide evidence that separate neural circuits perform the mathematically opposed operations of integration and segregation, by demonstrating with a dual-task paradigm that the two processes do not share attentional resources. Human observers attentively tracked a subset of target elements composing a small MOT stimulus, while pursuing it ocularly as it translated across a computer display. Integration of the multidot stimulus yielded optimal pursuit. Importantly, performing MOT while pursuing the stimulus did not degrade performance on either task compared with when each was performed alone, indicating that they did not share attention. A control experiment showed that pursuit was not driven by integration of only the nontargets, leaving the MOT targets free for segregation. Nor was a predictive strategy used to pursue the stimulus, because sudden changes in its global velocity were accurately followed. The results suggest that separate neural mechanisms can simultaneously segregate and integrate the same motion signals.