COMPARING RESTING BRAIN GLUCOSE METABOLISM IN MONKEYS, APES AND HUMANS

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。认知神经学家最近将注意力转向了人类的休息状态，他们认为存在一种默认的神经网络，它在休息时处于张力活跃状态。在这个休眠状态网络所涉及的大脑区域中，假设背内侧前额叶皮质与反映自我和他人的心理状态有关。考虑到它们社会生活的复杂性，以及它们潜在的自我意识能力，大猩猩也有可能默认进入一种涉及思考精神状态的休息状态模式。如果是这样的话，他们应该表现出与人类受试者相似的静息大脑新陈代谢模式。在这里，我们使用18F-FDG正电子发射断层扫描(PET)成像来比较猴子、猿猴和人类在静息状态下的局部脑葡萄糖代谢。我们收集了8名人类、5名黑猩猩和4名猕猴的扫描数据。猕猴用高分辨率、小动物专用的协和式microPET扫描仪(~2 mm半高宽)扫描，黑猩猩用西门子HRRT(高分辨率研究断层扫描仪，~2 mm半高宽)扫描，人类用ECAT Exact 921扫描仪(~5 mm半高宽)扫描。5%和1%的代谢最活跃的体素被识别并跨物种进行比较。这些分析揭示了不同物种之间共同的激活区域，以及物种激活的差异，这似乎与静止认知的差异有关。3个物种均表现出背外侧前额叶皮质(BA 46)的激活，只有人类和黑猩猩在与社会认知相关的前额内侧区域表现出激活，只有人类在Wernicke？S和Broca？S区表现出激活，这可能反映了一种内心的静息独白。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Cognitive neuroscientists have recently turned their attention to the resting state in humans, arguing for the existence of a default neural network that is tonically active at rest. Among the brain areas implicated in this resting state network, the dorsomedial prefrontal cortex is hypothesized to relate to reflecting on the mental states of self and others. Given the complexity of their social lives, as well as their potential capacity for self-awareness, it is possible that great apes also default to a resting state mode that involves thinking about mental states. If so, they should exhibit a similar pattern of resting brain metabolism as seen in human subjects. Here, we use 18F-FDG Positron Emission Tomography (PET) imaging to compare regional cerebral glucose metabolism at rest in monkeys, apes and humans. We collected scans from eight human, five chimpanzee and four macaque subjects. Macaques were scanned with a high resolution, small animal dedicated Concorde microPET scanner (~2 mm FWHM), chimpanzees were scanned with a Siemens HRRT (High Resolution Research Tomograph, ~2mm FWHM)), and humans were scanned with an ECAT EXACT 921 scanner (~5 mm FWHM). The 5% and 1% most metabolically active voxels were identified and compared across species. These analyses revealed common regions of activation across species, as well as species differences in activation that are plausibly related to differences in resting cognition. All three species showed dorsolateral prefrontal cortex (BA 46) activation, only humans and chimpanzees showed activation in medial prefrontal regions related to social cognition, and only humans showed activation in Wernicke?s and Broca?s areas that might reflect an inner mental monologue at rest.