Department of Biology, City College of New York, New York, New York; and PhD Program in Biology, The Graduate Center, City University of New York, New York, New York.
Department of Biology, City College of New York, New York, New York; and
J Neurophysiol. 2014 Jun 1;111(11):2307-19. doi: 10.1152/jn.00894.2013. Epub 2014 Mar 19.
The accuracy of saccades, as maintained by saccade adaptation, has been shown to be context dependent: able to have different amplitude movements to the same retinal displacement dependent on motor contexts such as orbital starting location. There is conflicting evidence as to whether purely visual cues also effect contextual saccade adaptation and, if so, what function this might serve. We tested what visual cues might evoke contextual adaptation. Over 5 experiments, 78 naive subjects made saccades to circularly moving targets, which stepped outward or inward during the saccade depending on target movement direction, speed, or color and shape. To test if the movement or context postsaccade were critical, we stopped the postsaccade target motion (experiment 4) or neutralized the contexts by equating postsaccade target speed to an intermediate value (experiment 5). We found contextual adaptation in all conditions except those defined by color and shape. We conclude that some, but not all, visual cues before the saccade are sufficient for contextual adaptation. We conjecture that this visual contextuality functions to allow for different motor states for different coordinated movement patterns, such as coordinated saccade and pursuit motor planning.
扫视的准确性，如扫视适应所维持的那样，被证明是依赖于上下文的：能够对相同的视网膜位移做出不同幅度的运动，这取决于运动上下文，例如轨道起始位置。关于纯粹的视觉线索是否也会影响上下文扫视适应，以及如果是这样，这可能会起到什么作用，存在相互矛盾的证据。我们测试了哪些视觉线索可能会引起上下文适应。在 5 个实验中，78 名未受过训练的受试者向圆形运动的目标进行扫视，目标在扫视期间会根据目标运动方向、速度或颜色和形状向外或向内移动。为了测试运动或上下文在扫视后是否关键，我们停止了扫视后的目标运动（实验 4），或者通过将扫视后的目标速度等同于中间值来使上下文中性化（实验 5）。我们发现除了颜色和形状定义的条件外，在所有条件下都存在上下文适应。我们得出结论，在扫视之前的某些，但不是所有的视觉线索，对于上下文适应是足够的。我们推测，这种视觉语境功能是为了允许不同的运动状态，用于不同的协调运动模式，例如协调扫视和追踪运动规划。
