Department of Psychological Sciences, University of Liverpool, Liverpool, L69 7ZA, UK.
Sci Rep. 2021 Jan 11;11(1):285. doi: 10.1038/s41598-020-79457-x.
Visual regularity activates a network of brain regions in the extrastriate cortex. Previous EEG studies have found that this response scales parametrically with proportion of symmetry in symmetry + noise displays. The parametric symmetry response happens in many tasks, but it is enhanced during active regularity discrimination. However, the origins and time course of this selective enhancement are unclear. Here we answered remaining questions with new source dipole analysis. As assumed, the parametric symmetry response found at the sensor level was generated by a pair of dipoles in the left and right extrastriate cortex. This bilateral activity was itself enhanced during regularity discrimination. However, we identified a third, and later, symmetry response in the posterior cingulate during regularity discrimination. Unlike the extrastriate response, this previously unknown activation only indexes strong, task relevant regularity signals. This clarifies the neural circuits which mediate the perceptual and cognitive aspects of symmetry discrimination.
视觉规则性激活了外纹状皮层中一组脑区。先前的脑电图研究发现，这种反应与对称+噪声显示中的对称比例呈参数化关系。这种参数化的对称性反应发生在许多任务中，但在主动规则性辨别中会增强。然而，这种选择性增强的起源和时程尚不清楚。在这里，我们用新的源偶极子分析回答了剩余的问题。正如假设的那样，在传感器水平上发现的参数化对称性反应是由左、右外纹状皮层中的一对偶极子产生的。这种双侧活动本身在规则性辨别中得到了增强。然而，我们在规则性辨别期间在后扣带回中识别出了第三个、更晚的对称性反应。与外纹状皮层反应不同，这种先前未知的激活仅索引强的、与任务相关的规则性信号。这阐明了介导对称性辨别的知觉和认知方面的神经回路。
