Reverse Correlation Mapping in Face Patches

描述(由申请者提供)：该项目的目标是探索经验、专业知识和颞叶模块化组织之间的关系。在过去的四年里，这个实验室探索了人脸检测和识别的功能解剖学和机制，目前的建议是将这些研究扩展到简单的形状，以及密集的早期经验在生成解剖学上独特的功能专门化领域中的作用。大脑中有不同的区域，可以从一个人复制到另一个人，专门处理最普遍形式的人类专业知识；例如，面部处理、语音处理和阅读。人类和猕猴都使用功能磁共振成像(FMRI)识别了颞叶中的面部选择性区域，在人类中，对字母和单词的视觉识别也局限在颞叶的同一部分，但更多的是侧面和后部，以及对侧半球。由于灵长类动物社会互动的重要性，人们可以想象自然选择会产生一个特定于面部的区域，但考虑到人类使用书面语言只有几千年，而识字最多也只有几百年，因此不太可能进化出特定于书面语的皮质区域。大多数人对面孔和符号都有密集的早期经验，这一事实引发了这样一个问题：密集的早期经验是否会导致猴子发展出处理它们从未自然使用的刺激的解剖学专门化。经过强化训练，幼猴学习符号的速度比成年猴子更快，对符号的反应也更流畅。此外，功能磁共振成像显示，青少年，而不是成年人，在他们的颞叶中形成了对学习符号有选择性地反应的区域，但对视觉上相似但不熟悉的符号没有反应。这为研究训练诱导的皮质模块的生理学和功能组织提供了独特的机会，该模块选择猴子通常不经历的简单形状，并将该区域与未经训练和后期训练的动物的相同皮质区域进行比较。单单位电生理学和功能磁共振成像将并行和联合使用，以探索这些训练诱导的符号识别区域的功能专门化，并探索早期和晚期训练的动物在颞叶相同部分的差异。未经训练、后期训练和早期训练的动物在这一区域的反应特性的差异将阐明经验如何与发育过程中的成熟梯度相互作用。学习的符号是简单的形状，简单的特征在学习的符号集中共享，因此单单位生理学应该揭示训练如何影响形状选择细胞结合简单特征以产生更复杂的形状选择的方式。这项拟议的研究应该会让人们更深入地理解早期的社会和教育经历或剥夺是如何影响发育中的大脑的。 与公共健康相关：拟议研究的目标是更深入地了解早期社会和教育经验以及剥夺的重要性和不可逆转性，通过机械地理解早期经验可以如何密集地改变大脑的模块化组织，并导致专家流利的处理特征技能，如人脸识别、语言和阅读。这对心理健康的影响是巨大的：如果需要密集的早期社会经验来发展面孔加工的功能分离，如果功能分离是熟练的面孔处理所必需的，那么早期社会经验的时间和数量可能在自闭症谱系障碍的病因和/或治疗中至关重要。早期的生活经历显然可以产生长期持久的后果，我们需要更好地理解某些经历的时机或缺乏，如何永久地改变大脑处理相应类型信息的方式。

DESCRIPTION (provided by applicant): The project goal is to explore the relationship between experience, expertise, and modular organization in the temporal lobe. During the last 4 years this laboratory has explored the functional anatomy and mechanisms of face detection and recognition, and the present proposal is to extend these studies to simple shapes and to the role of intensive early experience in generating anatomically distinct functionally specialized domains. There are distinct regions of the brain, reproducible from one person to the next, specialized for processing the most universal forms of human expertise; e.g., face processing, speech processing, and reading. Face-selective regions in the temporal lobe have been identified using functional magnetic resonance imaging (fMRI) in both humans and macaques, and in humans visual recognition of letters and words is also localized, to the same part of the temporal lobe, but more lateral and posterior and in the opposite hemisphere. Because of the importance of social interactions in primates, one could imagine a face-specific region being generated by natural selection, but it is unlikely that a cortical region specific for written words could have evolved, given that humans have been using written language for only a few thousand years, and literacy has been widespread for at most a few hundred years. The fact that most people have intensive early experience with both faces and symbols prompted the question of whether intensive early experience could cause monkeys to develop anatomical specializations for processing stimuli they never naturally use. After intensive training, juvenile monkeys learned symbols faster than adult monkeys and developed more "fluency" in responding to them. Furthermore fMRI revealed that juveniles, but not adults, develop regions in their temporal lobes selectively responsive to the learned symbols, but not to visually similar but unfamiliar symbols. This provides the unique opportunity to study the physiology and functional organization of a training-induced cortical module selective for simple shapes not normally experienced by monkeys, and to compare this region to the same cortical region in untrained and late-trained animals. Single-unit electrophysiology and fMRI will be used in parallel and in conjunction to explore the functional specialization in these training-induced symbol recognition regions and to explore the differences in the same parts of the temporal lobe in early versus late trained animals. Differences in response properties in this region between untrained, late trained, and early trained animals will illuminate how experience interacts with maturational gradients during development. The learned symbols are simple shapes, with simple features shared among the learned symbol set, therefore single unit physiology should reveal how training affects the way shape selective cells combine simple features to generate more complex shape selectivity. The proposed study should lead to a deeper understanding of how early social and educational experience or deprivation affects the developing brain. PUBLIC HEALTH RELEVANCE: The goal of the proposed research is to gain a deeper understanding of the importance and irreversibility of early social and educational experience and deprivation by providing a mechanistic understanding of how intensive early experience can modify the modular organization of the brain, and lead to the expert fluent processing characteristic skills like face recognition, language, and reading. The implications for mental health are enormous: if intensive early social experience is necessary to develop functional segregation of face processing, and if functional segregation is necessary for proficient face processing, then the timing and quantity of early social experience may be critical in the etiology and/or remediation of autism spectrum disorders. Early life experiences clearly can have long lasting consequences, and we need to better understand how the timing of some kinds of experience, or the lack thereof, can permanently change how the brain processes corresponding kinds of information.