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arXiv 0705.2913q-bio.NCq-bio.TO
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全球和区域脑代谢缩放及其功能后果

Global and regional brain metabolic scaling and its functional consequences

Jan Karbowski

摘要:

背景资料:大脑中的信息处理需要大量的代谢能量,其空间分布是高度不均匀的,反映了哺乳动物大脑中的复杂活动模式。结果如下:在此,基于经验数据发现,尽管存在这种异质性,但许多不同脑结构的体积特异性脑葡萄糖代谢率与脑体积成比例,具有几乎相同的指数约为-0.15。例外的是白质,其代谢似乎与标准特定指数-1/4成比例。脑中总氧和葡萄糖消耗量相对于其体积的标度指数是相同的,等于$0.86\pm 0.03$,其显著大于全身基础代谢对体重的指数3/4和2/3。结论:这些研究结果明确表明,在哺乳动物中(i)不同脑部位的脑能量消耗的体积特异性标度指数近似恒定(脑干结构除外),以及(ii)总脑代谢指数对脑体积大于被广泛引用的Kleiber的3/4指数。的神经生理因素,可能占区域的均匀性的指数和过度缩放的总脑代谢进行了讨论,以及脑代谢缩放和计算之间的关系。

英文摘要:

Background: Information processing in the brain requires large amounts of metabolic energy, the spatial distribution of which is highly heterogeneous reflecting complex activity patterns in the mammalian brain. Results: Here, it is found based on empirical data that, despite this heterogeneity, the volume-specific cerebral glucose metabolic rate of many different brain structures scales with brain volume with almost the same exponent around -0.15. The exception is white matter, the metabolism of which seems to scale with a standard specific exponent -1/4. The scaling exponents for the total oxygen and glucose consumptions in the brain in relation to its volume are identical and equal to $0.86\pm 0.03$, which is significantly larger than the exponents 3/4 and 2/3 suggested for whole body basal metabolism on body mass. Conclusions: These findings show explicitly that in mammals (i) volume-specific scaling exponents of the cerebral energy expenditure in different brain parts are approximately constant (except brain stem structures), and (ii) the total cerebral metabolic exponent against brain volume is greater than the much-cited Kleiber's 3/4 exponent. The neurophysiological factors that might account for the regional uniformity of the exponents and for the excessive scaling of the total brain metabolism are discussed, along with the relationship between brain metabolic scaling and computation.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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