Dynamic models of BOLD contrast.
Dynamic models of BOLD contrast.
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DOI：
10.1016/j.neuroimage.2012.01.012
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发表时间：
2012-08-15
期刊：
影响因子：
5.7
通讯作者：
Buxton, Richard B.
中科院分区：
文献类型：
--
作者：
Buxton, Richard B.
关键词：
这个个人的回忆着眼于血液氧合水平依赖（BOLD）信号的动态思想的演变，重点是气球模型。从BOLD响应的第一次检测中可以清楚地看出，该信号表现出有趣的动态，例如明显且持久的刺激后下冲。BOLD反应反映了局部脱氧血红蛋白的变化，是与血流和静脉血容量变化相关的血液动力学反应和与氧代谢相关的代谢反应的组合。建模可能是理解从神经活动变化到BOLD信号的复杂路径的一种方法。在功能磁共振成像的早期，人们希望血流动力学/代谢反应能够以一种统一的方式建模，血流量，氧代谢和静脉血容量-影响局部脱氧血红蛋白的生理因素-都紧密相连。球囊模型是一种尝试，基于基线时有限的氧气输送和刺激后静脉血容量缓慢恢复的生理学想法（球囊效应），这种简单的生理学模型很好地模拟了BOLD反应。然而，随后的实验提出了一个更复杂的潜在生理学图像，血液流动和氧代谢并行驱动，可能是由神经活动的不同方面。此外，目前尚不清楚刺激后下冲是血液动力学还是代谢现象，尽管原始静脉球囊效应不太可能是完整的解释，并且流量下冲可能很重要。虽然我们对BOLD反应的物理学的理解现在相当扎实，但我们对潜在的生理关系的理解仍然相对较差，这是未来BOLD动力学模型的主要障碍。
This personal recollection looks at the evolution of ideas about the dynamics of the blood oxygenation level dependent (BOLD) signal, with an emphasis on the balloon model. From the first detection of the BOLD response it has been clear that the signal exhibits interesting dynamics, such as a pronounced and long-lasting post-stimulus undershoot. The BOLD response, reflecting a change in local deoxyhemoglobin, is a combination of a hemodynamic response, related to changes in blood flow and venous blood volume, and a metabolic response related to oxygen metabolism. Modeling is potentially a way to understand the complex path from changes in neural activity to the BOLD signal. In the early days of fMRI it was hoped that the hemodynamic/metabolic response could be modeled in a unitary way, with blood flow, oxygen metabolism, and venous blood volume—the physiological factors that affect local deoxyhemoglobin—all tightly linked. The balloon model was an attempt to do this, based on the physiological ideas of limited oxygen delivery at baseline and a slow recovery of venous blood volume after the stimulus (the balloon effect), and this simple model of the physiology worked well to simulate the BOLD response. However, subsequent experiments suggest a more complicated picture of the underlying physiology, with blood flow and oxygen metabolism driven in parallel, possibly by different aspects of neural activity. In addition, it is still not clear whether the post-stimulus undershoot is a hemodynamic or a metabolic phenomenon, although the original venous balloon effect is unlikely to be the full explanation, and a flow undershoot is likely to be important. Although our understanding of the physics of the BOLD response is now reasonably solid, our understanding of the underlying physiological relationships is still relatively poor, and this is the primary hurdle for future models of BOLD dynamics.
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DOI：
10.3389/fnene.2010.00008
发表时间：
2010
期刊：
Frontiers in neuroenergetics
影响因子：
--
作者：
Buxton RB
通讯作者：
Buxton RB
影响因子：
5.7
作者：
Chen BR;Bouchard MB;McCaslin AF;Burgess SA;Hillman EM
通讯作者：
Hillman EM
DOI：
10.1097/00004647-199701000-00009
发表时间：
1997-01-01
影响因子：
6.3
作者：
Buxton, RB;Frank, LR
通讯作者：
Frank, LR
DOI：
10.1073/pnas.83.4.1140
发表时间：
1986-02-01
影响因子：
11.1
作者：
FOX, PT;RAICHLE, ME
通讯作者：
RAICHLE, ME
影响因子：
5.7
作者：
Blockley, N. P.;Francis, S. T.;Gowland, P. A.
通讯作者：
Gowland, P. A.