COMPARING RESTING BRAIN GLUCOSE METABOLISM IN MONKEYS, APES AND HUMANS

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。认知神经科学家最近将注意力转向了人类的静息状态，认为存在一个默认的神经网络，在静息状态下是紧张性活跃的。在涉及这种静息状态网络的大脑区域中，背内侧前额叶皮层被假设与反思自我和他人的精神状态有关。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，有可能类人猿也默认了一种涉及思考精神状态的休息状态模式。如果是这样的话，它们应该表现出与人类受试者相似的静息脑代谢模式。在这里，我们使用18F-FDG正电子发射断层扫描（PET）成像比较猴子，猿和人类在休息时的局部脑葡萄糖代谢。 我们收集了8名人类，5只黑猩猩和4只猕猴的扫描结果。用高分辨率、小动物专用Concorde microPET扫描仪（~2 mm FWHM）扫描猕猴，用Siemens HRRT（高分辨率研究断层扫描仪，~ 2 mm FWHM）扫描黑猩猩，用ECAT EXACT 921扫描仪（~5 mm FWHM）扫描人类。 确定了5%和1%最具代谢活性的体素，并在不同物种之间进行了比较。这些分析揭示了跨物种激活的共同区域，以及与静息认知差异相关的激活的物种差异。这三个物种都表现出背外侧前额叶皮层（BA 46）激活，只有人类和黑猩猩表现出激活内侧前额叶区域相关的社会认知，只有人类表现出激活韦尼克？s和布罗卡？这些区域可能反映了休息时的内心独白。

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.