Department of Psychology, University of California, Los Angeles.
J Exp Psychol Gen. 2018 Sep;147(9):1295-1308. doi: 10.1037/xge0000409. Epub 2018 Apr 9.
The ability to form shape representations from visual input is crucial to perception, thought, and action. Perceived shape is abstract, as evidenced when we can see a contour specified only by discrete dots, when a cloud appears to resemble a fish, or when we match shapes across transformations of scale and orientation. Surprisingly little is known about the formation of abstract shape representations in biological vision. We report experiments that demonstrate the existence of abstract shape representations in visual perception and identify the time course of their formation. In Experiment 1, we varied stimulus exposure time in a task that required abstract shape and found that it emerges about 100 ms after stimulus onset. The results also showed that abstract shape representations are invariant across certain transformations and that they can be recovered from spatially separated dots. Experiment 2 found that encoding of basic visual features, such as dot locations, occurs during the first 30 ms after stimulus onset, indicating that shape representations require processing time beyond that needed to extract spatial features. Experiment 3 used a convergent method to confirm the timing and importance of abstract shape representations. Given sufficient time, shape representations form automatically and obligatorily, affecting performance even in a task in which neither instructions nor accurate responding involved shape. These results provide evidence for the existence, emergence, and functional importance of abstract shape representations in visual perception. We contrast these results with "deep learning" systems and with proposals that deny the importance of abstract representations in human perception and cognition. (PsycINFO Database Record
从视觉输入中形成形状表示的能力对于感知、思维和行动至关重要。感知到的形状是抽象的，这一点可以从以下事实中得到证明：我们可以看到仅由离散点指定的轮廓，当一朵云看起来像鱼时，或者当我们在尺度和方向的变换中匹配形状时。然而，关于生物视觉中抽象形状表示的形成，人们知之甚少。我们报告了一些实验，这些实验证明了抽象形状表示在视觉感知中的存在，并确定了它们形成的时间过程。在实验 1 中，我们在一个需要抽象形状的任务中改变了刺激暴露时间，发现它大约在刺激开始后 100 毫秒出现。结果还表明，抽象形状表示是不变的，可以从空间上分离的点中恢复。实验 2 发现，基本视觉特征（如点位置）的编码发生在刺激开始后的前 30 毫秒内，这表明形状表示需要超过提取空间特征所需的处理时间。实验 3 使用了一种收敛方法来确认抽象形状表示的时间和重要性。给定足够的时间，形状表示会自动形成，即使在一个既不需要形状指示也不需要准确响应的任务中，也会影响性能。这些结果为视觉感知中抽象形状表示的存在、出现和功能重要性提供了证据。我们将这些结果与“深度学习”系统以及否认抽象表示在人类感知和认知中的重要性的观点进行了对比。
