Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran 14115-111, Iran.
School of Cognitive Sciences, Institute for Research in Fundamental Sciences, Tehran 19395-5746, Iran.
Proc Natl Acad Sci U S A. 2024 Nov 26;121(48):e2407457121. doi: 10.1073/pnas.2407457121. Epub 2024 Nov 18.
Primates are known for their exceptional ability to recognize faces. However, we still have much to learn about how their brains process faces when they are partially hidden. When we cover parts of a face, it affects how our brains respond, even though we still perceive the face as a whole. This suggests that complex brain networks are at work in understanding partially hidden faces. To explore this further, we studied two brain regions, the ventrolateral prefrontal cortex (vlPFC) and the inferior temporal cortex (ITC), while showing primate images of faces with parts occluded. We found that vlPFC neurons were more active when faces were partially covered, while ITC neurons preferred fully visible faces. Interestingly, the ITC seemed to process occluded faces in a separate phase after the vlPFC responded. Our research revealed a coordinated effort between these brain regions based on the level of facial obstruction. Specifically, the vlPFC seemed to play a crucial role, driving the representation of occluded faces in the later phase of ITC processing. Importantly, we also found that the brain processes occluded faces differently from those that are fully visible, suggesting specialized mechanisms for handling these situations. These findings highlight the importance of feedback from the vlPFC in understanding occluded faces in the ITC region of the brain. Understanding these neural processes not only enhances our understanding of how primates perceive faces but also provides insights into broader aspects of visual cognition.
灵长类动物以其出色的面部识别能力而闻名。然而，当面部部分被遮挡时，我们仍有很多关于它们大脑如何处理面部的信息需要了解。当我们遮住脸的一部分时，即使我们仍然将其视为一个整体，它也会影响我们大脑的反应。这表明在理解部分遮挡的面部时，复杂的大脑网络在起作用。为了进一步探索这一点，我们研究了两个大脑区域，即腹外侧前额叶皮层（vlPFC）和下颞叶皮层（ITC），同时显示了带有部分遮挡的灵长类动物面部图像。我们发现，当面部被部分遮挡时，vlPFC 神经元更加活跃，而 ITC 神经元则更喜欢完全可见的面部。有趣的是，在 vlPFC 做出反应后，ITC 似乎会在一个单独的阶段处理被遮挡的面部。我们的研究揭示了这些大脑区域之间基于面部遮挡程度的协调努力。具体来说，vlPFC 似乎在 ITC 处理的后期阶段发挥了关键作用，推动了对遮挡面部的表示。重要的是，我们还发现大脑对遮挡的面部和完全可见的面部的处理方式不同，这表明存在专门的机制来处理这些情况。这些发现强调了来自 vlPFC 的反馈在理解大脑 ITC 区域中的遮挡面部的重要性。了解这些神经过程不仅增强了我们对灵长类动物如何感知面部的理解，还为更广泛的视觉认知方面提供了深入的见解。
