Cortical depth-dependent temporal dynamics of the BOLD response in the human brain
Cortical depth-dependent temporal dynamics of the BOLD response in the human brain
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DOI：
10.1038/jcbfm.2011.57
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发表时间：
2011-10-01
影响因子：
6.3
通讯作者：
Ramsey, Nick F.
中科院分区：
文献类型：
--
作者：
Siero, Jeroen C. W.;Petridou, Natalia;Ramsey, Nick F.
最近在高场下的动物研究表明，血氧水平依赖(BOLD)对比可以通过其参照皮质深度的时间动力学的差异而特定于大脑皮层的层状血管结构。在这项研究中，我们使用非常短的刺激和高空间和时间分辨率，在7T下，表征了人类初级运动和视皮层皮质深度的血液动力学反应(HDR)的时间动力学特征。我们发现，HDR的形状和时间动力学在大脑皮层深度上以有序的方式变化。与软脑膜血管系统相比，灰质深层的HDR在起效时间(接近0.5秒)和峰值时间(接近2秒)上显著加快，并且更窄(接近1秒)且幅度更小，这与已知的跨皮质深度的血管组织和脱氧血液通过血管系统的情况相一致。深部灰质中HDR的宽度只有2.1秒，这表明神经血管耦合发生的时间比之前在人脑中报道的更短。这些发现为探索人类灰质中特定层级的血流动力学和神经血管耦合机制提供了可能性。《脑血流与代谢杂志》(2011年)31期，1999年至2008年；DOI：10.1038/jcbfm.2011.57；2011年4月20日在线发表
Recent animal studies at high field have shown that blood oxygen level-dependent (BOLD) contrast can be specific to the laminar vascular architecture of the cortex, by differences in its temporal dynamics in reference to cortical depth. In this study, we characterize the temporal dynamics of the hemodynamic response (HDR) across cortical depth in the human primary motor and visual cortex, at 7 T and using very short stimuli and with high spatial and temporal resolution. We find that the shape and temporal dynamics of the HDR changed in an orderly manner across cortical depth. Compared with the pial vasculature, HDRs in deeper gray matter are significantly faster in onset time (by similar to 0.5 second) and peak time (similar to 2 seconds), and are narrower (by similar to 1 second) and with smaller amplitude, in line with the known vascular organization across cortical depth and the transit of deoxygenated blood through the vasculature. The width of the HDR in deeper gray matter was as short as 2.1 seconds, indicating that neurovascular coupling takes place at a shorter timescale than previously reported in the human brain. These findings open the possibility to probe layer-specific hemodynamics and neurovascular coupling mechanisms in human gray matter. Journal of Cerebral Blood Flow & Metabolism (2011) 31, 1999-2008; doi:10.1038/jcbfm.2011.57; published online 20 April 2011