Murray Scott O, Kersten Daniel, Olshausen Bruno A, Schrater Paul, Woods David L
Center for Neuroscience, Department of Psychology, University of California, Davis 95616, USA.
Proc Natl Acad Sci U S A. 2002 Nov 12;99(23):15164-9. doi: 10.1073/pnas.192579399. Epub 2002 Nov 4.
Visual perception involves the grouping of individual elements into coherent patterns that reduce the descriptive complexity of a visual scene. The physiological basis of this perceptual simplification remains poorly understood. We used functional MRI to measure activity in a higher object processing area, the lateral occipital complex, and in primary visual cortex in response to visual elements that were either grouped into objects or randomly arranged. We observed significant activity increases in the lateral occipital complex and concurrent reductions of activity in primary visual cortex when elements formed coherent shapes, suggesting that activity in early visual areas is reduced as a result of grouping processes performed in higher areas. These findings are consistent with predictive coding models of vision that postulate that inferences of high-level areas are subtracted from incoming sensory information in lower areas through cortical feedback.
视觉感知涉及将单个元素组合成连贯的模式，从而降低视觉场景的描述复杂性。这种感知简化的生理基础仍知之甚少。我们使用功能磁共振成像来测量一个更高层次的物体处理区域——外侧枕叶复合体，以及初级视觉皮层对视觉元素的活动，这些视觉元素要么被组合成物体，要么是随机排列的。当元素形成连贯形状时，我们观察到外侧枕叶复合体的活动显著增加，同时初级视觉皮层的活动减少，这表明早期视觉区域的活动因更高层次区域执行的分组过程而减少。这些发现与视觉的预测编码模型一致，该模型假设通过皮层反馈，将高层次区域的推断从低层次区域传入的感觉信息中减去。
