Functional Subdomains within Human FFA
Functional Subdomains within Human FFA
复制标题
DOI：
10.1523/jneurosci.1259-13.2013
复制
发表时间：
2013-10-16
影响因子：
5.3
通讯作者：
Gallant, Jack L.
中科院分区：
文献类型：
--
作者：
Cukur, Tolga;Huth, Alexander G.;Gallant, Jack L.
梭形脸部区域(FFA)是人类大脑中一个被充分研究的区域，它显示出对面孔的强烈激活。在功能磁共振研究中，FFA通常被认为是具有相似视觉调节的同质体素集合。为了测试这一假设，我们使用自然电影和量化的体素建模和解码框架来估计FFA中单个体素的类别调整配置文件。我们发现，正如以前的研究所报道的那样，大多数FFA体素的反应都被人脸强烈地增强了。然而，我们也发现，单个体素的响应被各种各样的其他类别选择性地增强或抑制，并且这些更广泛的调谐轮廓在FFA体素中是不同的。跨体素的类别调谐配置文件的聚类分析揭示了FFA中三个空间分离的功能亚域。这些子域的主要不同之处在于它们对非人脸类别的反应，如动物、车辆和交流动词。此外，这种分离不依赖于用于根据对功能定位子的响应来定义FFA的统计阈值。这些结果表明，FFA中的体素代表了关于对象和动作类别的更多样化的信息，而不是通常假设的信息。
The fusiform face area (FFA) is a well-studied human brain region that shows strong activation for faces. In functional MRI studies, FFA is often assumed to be a homogeneous collection of voxels with similar visual tuning. To test this assumption, we used natural movies and a quantitative voxelwise modeling and decoding framework to estimate category tuning profiles for individual voxels within FFA. We find that the responses in most FFA voxels are strongly enhanced by faces, as reported in previous studies. However, we also find that responses of individual voxels are selectively enhanced or suppressed by a wide variety of other categories and that these broader tuning profiles differ across FFA voxels. Cluster analysis of category tuning profiles across voxels reveals three spatially segregated functional subdomains within FFA. These subdomains differ primarily in their responses for nonface categories, such as animals, vehicles, and communication verbs. Furthermore, this segregation does not depend on the statistical threshold used to define FFA from responses to functional localizers. These results suggest that voxels within FFA represent more diverse information about object and action categories than generally assumed.