Barron Helen C, Garvert Mona M, Behrens Timothy E J
MRC Brain Network Dynamics Unit, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3TH, UK Oxford Centre for Functional MRI of the Brain, Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London, London WC1N 3BG, UK.
Philos Trans R Soc Lond B Biol Sci. 2016 Oct 5;371(1705). doi: 10.1098/rstb.2015.0355.
Understanding how the human brain gives rise to complex cognitive processes remains one of the biggest challenges of contemporary neuroscience. While invasive recording in animal models can provide insight into neural processes that are conserved across species, our understanding of cognition more broadly relies upon investigation of the human brain itself. There is therefore an imperative to establish non-invasive tools that allow human brain activity to be measured at high spatial and temporal resolution. In recent years, various attempts have been made to refine the coarse signal available in functional magnetic resonance imaging (fMRI), providing a means to investigate neural activity at the meso-scale, i.e. at the level of neural populations. The most widely used techniques include repetition suppression and multivariate pattern analysis. Human neuroscience can now use these techniques to investigate how representations are encoded across neural populations and transformed by relevant computations. Here, we review the physiological basis, applications and limitations of fMRI repetition suppression with a brief comparison to multivariate techniques. By doing so, we show how fMRI repetition suppression holds promise as a tool to reveal complex neural mechanisms that underlie human cognitive function.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'.
理解人类大脑如何产生复杂的认知过程仍然是当代神经科学面临的最大挑战之一。虽然在动物模型中进行侵入性记录可以深入了解跨物种保守的神经过程，但我们对认知的更广泛理解更多地依赖于对人类大脑本身的研究。因此，迫切需要建立非侵入性工具，以便能够在高空间和时间分辨率下测量人类大脑活动。近年来，人们进行了各种尝试来优化功能磁共振成像（fMRI）中可用的粗糙信号，提供了一种在中尺度水平，即神经群体水平上研究神经活动的方法。最广泛使用的技术包括重复抑制和多变量模式分析。人类神经科学现在可以使用这些技术来研究表征如何在神经群体中编码以及如何通过相关计算进行转换。在这里，我们回顾fMRI重复抑制的生理基础、应用和局限性，并与多变量技术进行简要比较。通过这样做，我们展示了fMRI重复抑制作为揭示人类认知功能背后复杂神经机制的工具具有怎样的前景。本文是主题为“解读血氧水平依赖信号：认知神经科学与细胞神经科学之间的对话”的特刊的一部分。
