Ratan Murty N Apurva, Arun S P
Centre for Neuroscience, Indian Institute of Science, Bangalore, India.
Centre for Neuroscience, Indian Institute of Science, Bangalore, India
J Neurophysiol. 2017 Jan 1;117(1):104-116. doi: 10.1152/jn.00551.2016. Epub 2016 Oct 12.
We have no difficulty seeing a straight line drawn on a paper even when the paper is bent, but this inference is in fact nontrivial. Doing so requires either matching local features or representing the pattern after factoring out the surface shape. Here we show that single neurons in the monkey inferior temporal (IT) cortex show invariant responses to patterns across rigid and nonrigid changes of surfaces. We recorded neuronal responses to stimuli in which the pattern and the surrounding surface were varied independently. In a subset of neurons, we found pattern-surface interactions that produced similar responses to stimuli across congruent pattern and surface transformations. These interactions produced systematic shifts in curvature tuning of patterns when overlaid on convex and flat surfaces. Our results show that surfaces are factored out of patterns by single neurons, thereby enabling complex perceptual inferences.
NEW & NOTEWORTHY: We have no difficulty seeing a straight line on a curved piece of paper, but in fact, doing so requires decoupling the shape of the surface from the pattern itself. Here we report a novel form of invariance in the visual cortex: single neurons in monkey inferior temporal cortex respond similarly to congruent transformations of patterns and surfaces, in effect decoupling patterns from the surface on which they are overlaid.
即使纸张弯曲，我们也能毫不费力地看到画在纸上的直线，但实际上这种推断并非易事。要做到这一点，要么匹配局部特征，要么在排除表面形状后表示图案。在这里，我们表明，猴子颞下（IT）皮质中的单个神经元对跨刚性和非刚性表面变化的图案表现出不变的反应。我们记录了神经元对图案和周围表面独立变化的刺激的反应。在一部分神经元中，我们发现了图案 - 表面相互作用，这种相互作用对全等图案和表面变换的刺激产生相似的反应。当图案叠加在凸面和平面上时，这些相互作用会使图案的曲率调谐产生系统性变化。我们的结果表明，单个神经元能够从图案中排除表面因素，从而实现复杂的感知推断。
我们能毫不费力地在弯曲的纸上看到一条直线，但实际上，这样做需要将表面形状与图案本身解耦。在这里，我们报告了视觉皮质中一种新的不变性形式：猴子颞下皮质中的单个神经元对图案和表面的全等变换有相似的反应，实际上是将图案与它们所叠加的表面解耦。
