Cortical Representations of Symbols, Objects, and Faces Are Pruned Back during Early Childhood
Cortical Representations of Symbols, Objects, and Faces Are Pruned Back during Early Childhood
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DOI：
10.1093/cercor/bhq078
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发表时间：
2011-01-01
期刊：
影响因子：
3.7
通讯作者：
Pelphrey, Kevin A.
中科院分区：
文献类型：
--
作者：
Cantlon, Jessica F.;Pinel, Philippe;Pelphrey, Kevin A.
人类腹侧纹状体视觉皮层区域发展了自然类别（例如面部）和文化制品（例如单词）的专业化。在成年人中，基于类别的专业化表现为大脑视觉区域（例如梭状回）对某些类别的神经反应比其他类别更强。然而，很少有研究探讨这些专业化是如何起源于儿童大脑的。此外，目前尚不清楚视觉专业化的发展是否取决于对首选类别的反应“增加”，对非首选类别的反应“减少”，或“两者兼而有之”。这个问题与关于神经发育是否是通过建立或修剪表征来驱动的长期争论有关。为了探索这些问题，我们使用功能磁共振成像测量了 4 岁儿童 4 类（面孔、字母、数字和鞋子）的视觉活动模式。我们报告了关于大脑中视觉类别发展的两个关键发现：1）在儿童能够阅读之前，“面孔”和“符号”类别在梭状回中双重分离；2）幼儿类别特异性反应的发展取决于对非偏好类别的皮层反应，随着偏好类别知识的获得，这种反应会减少。
Regions of human ventral extrastriate visual cortex develop specializations for natural categories (e.g., faces) and cultural artifacts (e.g., words). In adults, category-based specializations manifest as greater neural responses in visual regions of the brain (e.g., fusiform gyrus) to some categories over others. However, few studies have examined how these specializations originate in the brains of children. Moreover, it is as yet unknown whether the development of visual specializations hinges on "increases" in the response to the preferred categories, "decreases" in the responses to nonpreferred categories, or "both." This question is relevant to a long-standing debate concerning whether neural development is driven by building up or pruning back representations. To explore these questions, we measured patterns of visual activity in 4-year-old children for 4 categories (faces, letters, numbers, and shoes) using functional magnetic resonance imaging. We report 2 key findings regarding the development of visual categories in the brain: 1) the categories "faces" and "symbols" doubly dissociate in the fusiform gyrus before children can read and 2) the development of category-specific responses in young children depends on cortical responses to nonpreferred categories that decrease as preferred category knowledge is acquired.