Dense sampling reveals behavioral oscillations in rapid visual categorization.
Dense sampling reveals behavioral oscillations in rapid visual categorization.
复制标题
密集采样揭示快速视觉分类中的行为振荡
DOI：
10.1038/srep16290
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发表时间：
2015-11-06
影响因子：
4.6
通讯作者：
Melcher D
中科院分区：
文献类型：
--
作者：
Drewes J;Zhu W;Wutz A;Melcher D
感知系统必须从连续的感觉信息流中创造出离散的对象和事件。先前的研究已经证明了低水平视觉任务的行为结果中的振荡效应，这表明视觉处理的周期性本质是解决方案。为了研究这些影响是否延伸到更复杂的任务，一个“中性”的摄影图像流（不包含目标）迅速提出（20毫秒/图像）。嵌入的是一个或两个随机选择的目标图像（车辆和动物）的介绍。受试者报告了感知的目标类别。在双呈现试验中，ISI从0到600 ms系统地变化。在第一个目标呈现之前的随机定时，屏幕闪烁，目的是在视觉系统中创建相位重置。闪光灯和第一个目标呈现之间的时间距离的排序试验显示，在行为表现的强烈振荡，峰值在5赫兹。在双靶试验中，较长的ISI导致性能降低，这意味着对象类别歧视的时间整合窗口。“动物”试验在5 Hz左右显示出显著的振荡分量。我们的研究结果表明，振荡效应不仅仅是边缘效应相关的简单刺激，但从视觉处理的核心机制，并可能扩展到现实生活中的场景。
Perceptual systems must create discrete objects and events out of a continuous flow of sensory information. Previous studies have demonstrated oscillatory effects in the behavioral outcome of low-level visual tasks, suggesting a cyclic nature of visual processing as the solution. To investigate whether these effects extend to more complex tasks, a stream of “neutral” photographic images (not containing targets) was rapidly presented (20 ms/image). Embedded were one or two presentations of a randomly selected target image (vehicles and animals). Subjects reported the perceived target category. On dual-presentation trials, the ISI varied systematically from 0 to 600 ms. At randomized timing before first target presentation, the screen was flashed with the intent of creating a phase reset in the visual system. Sorting trials by temporal distance between flash and first target presentation revealed strong oscillations in behavioral performance, peaking at 5 Hz. On dual-target trials, longer ISIs led to reduced performance, implying a temporal integration window for object category discrimination. The “animal” trials exhibited a significant oscillatory component around 5 Hz. Our results indicate that oscillatory effects are not mere fringe effects relevant only with simple stimuli, but are resultant from the core mechanisms of visual processing and may well extend into real-life scenarios.