Zhang Jiedong, Liu Jia, Xu Yaoda
Department of Psychology, Harvard University, Cambridge, Massachusetts 02138, and.
State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, 100875 Beijing, China.
J Neurosci. 2015 Jan 28;35(4):1539-48. doi: 10.1523/JNEUROSCI.2646-14.2015.
Most of human daily social interactions rely on the ability to successfully recognize faces. Yet ∼2% of the human population suffers from face blindness without any acquired brain damage [this is also known as developmental prosopagnosia (DP) or congenital prosopagnosia]). Despite the presence of severe behavioral face recognition deficits, surprisingly, a majority of DP individuals exhibit normal face selectivity in the right fusiform face area (FFA), a key brain region involved in face configural processing. This finding, together with evidence showing impairments downstream from the right FFA in DP individuals, has led some to argue that perhaps the right FFA is largely intact in DP individuals. Using fMRI multivoxel pattern analysis, here we report the discovery of a neural impairment in the right FFA of DP individuals that may play a critical role in mediating their face-processing deficits. In seven individuals with DP, we discovered that, despite the right FFA's preference for faces and it showing decoding for the different face parts, it exhibited impaired face configural decoding and did not contain distinct neural response patterns for the intact and the scrambled face configurations. This abnormality was not present throughout the ventral visual cortex, as normal neural decoding was found in an adjacent object-processing region. To our knowledge, this is the first direct neural evidence showing impaired face configural processing in the right FFA in individuals with DP. The discovery of this neural impairment provides a new clue to our understanding of the neural basis of DP.
人类的大多数日常社交互动都依赖于成功识别人脸的能力。然而，约2%的人口在没有任何后天性脑损伤的情况下患有脸盲症（这也被称为发育性面孔失认症或先天性面孔失认症）。尽管存在严重的行为性人脸识别缺陷，但令人惊讶的是，大多数发育性面孔失认症患者在右侧梭状面孔区（FFA）表现出正常的面孔选择性，右侧梭状面孔区是参与面孔结构加工的关键脑区。这一发现，连同表明发育性面孔失认症患者右侧梭状面孔区下游存在损伤的证据，使得一些人认为发育性面孔失认症患者的右侧梭状面孔区可能在很大程度上是完整的。利用功能磁共振成像多体素模式分析，我们在此报告了发育性面孔失认症患者右侧梭状面孔区存在神经损伤，这可能在介导他们的面孔加工缺陷中起关键作用。在7名发育性面孔失认症患者中，我们发现，尽管右侧梭状面孔区对面孔有偏好并且显示出对不同面部部位的解码能力，但它表现出面孔结构解码受损，并且对于完整和打乱的面孔配置没有包含不同的神经反应模式。这种异常并非存在于整个腹侧视觉皮层，因为在相邻的物体加工区域发现了正常的神经解码。据我们所知，这是首个直接的神经证据，表明发育性面孔失认症患者右侧梭状面孔区的面孔结构加工受损。这一神经损伤的发现为我们理解发育性面孔失认症的神经基础提供了新线索。
