Department of Neurobiology, Weizmann Institute of Science, 76100 Rehovot, Israel.
Department of Neurobiology, Weizmann Institute of Science, 76100 Rehovot, Israel.
Neuroimage. 2015 Feb 1;106:414-27. doi: 10.1016/j.neuroimage.2014.11.034. Epub 2014 Nov 20.
Even in absence of overt tasks, the human cortex manifests rich patterns of spontaneous "resting state" BOLD-fMRI fluctuations. However, the link of these spontaneous fluctuations to behavior is presently unclear. Attempts to directly investigate this link invariably lead to disruptions of the resting state. Here we took advantage of the well-established association between pupil diameter and attentional gain to address this issue by examining the correlation between the resting state BOLD and pupil fluctuations. Our results uncover a spontaneously emerging spatiotemporal pupil-BOLD correlation whereby a slow buildup of activity in default mode areas preceded both pupil dilation and wide-spread BOLD suppression in sensorimotor cortex. Control experiments excluded a role for luminance fluctuations or fixation. Comparing the pupil-correlated patterns to activation maps during visual imagery revealed a substantial overlap. Our results indicate a link between behavior, as indexed by pupil diameter, and resting state BOLD fluctuations. These pupil dilations, assumed to be related to attentional gain, were associated with spontaneously emerging antagonism between fundamental cortical networks.
即使没有明显的任务，人类大脑皮层也会表现出丰富的自发“静息状态”BOLD-fMRI 波动模式。然而，这些自发波动与行为之间的联系目前还不清楚。目前，人们试图直接研究这种联系，往往会破坏静息状态。在这里，我们利用瞳孔直径与注意力增益之间的既定关联，通过检查静息状态 BOLD 与瞳孔波动之间的相关性来解决这个问题。我们的研究结果揭示了一种自发出现的时空瞳孔-BOLD 相关性，即默认模式区域的活动缓慢积累，先于瞳孔扩张和感觉运动皮层的广泛 BOLD 抑制。控制实验排除了亮度波动或固定的作用。将与瞳孔相关的模式与视觉想象期间的激活图进行比较，发现有很大的重叠。我们的研究结果表明，行为（以瞳孔直径为指标）与静息状态 BOLD 波动之间存在联系。这些被认为与注意力增益有关的瞳孔扩张，与基本皮质网络之间自发出现的拮抗作用有关。
