Disparity of activation onset in sensory cortex from simultaneous auditory and visual stimulation: Differences between perfusion and blood oxygenation level-dependent functional magnetic resonance imaging.
Disparity of activation onset in sensory cortex from simultaneous auditory and visual stimulation: Differences between perfusion and blood oxygenation level-dependent functional magnetic resonance imaging.
复制标题
同时听觉和视觉刺激引起的感觉皮层激活起始的差异：灌注和血氧水平依赖性功能磁共振成像之间的差异。
DOI：
10.1002/jmri.20242
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Gao,Jia-Hong
中科院分区：
文献类型：
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作者：
Liu,Ho-Ling;Feng,Ching-Mei;Li,Jinqi;Su,Fan-Chi;Li,Ning;Glahn,David;Gao,Jia-Hong
目的比较灌注和血氧水平依赖（BOLD）功能磁共振成像（fMRI）检测不同脑区时间差异的时间行为，材料和方法反转恢复（IR）自旋回波回波平面成像（EPI）和T2 *分别使用加权梯度回波EPI序列进行灌注和BOLD加权实验。在事件相关（ER）范式中同时采用听觉和视觉刺激。在40次重复试验中对信号时间过程进行平均，以评估激活的开始，并确定听觉和视觉皮层之间以及这些扫描方法之间的激活潜伏期的潜在差异。（均方根（RMS）= 134毫秒）和-80至930毫秒（RMS = 604毫秒）。BOLD序列检测到的时间变异性在受试者之间更大，并且显著大于灌注反应（P <0.04）。灌注成像的半峰时间（TTHM）测量值（视觉，3260 ± 710毫秒;听觉，3130 ± 700毫秒）早于BOLD反应（视觉，3770 ± 430毫秒;听觉，3360 ± 460毫秒）结论BOLD检测到的脑区之间更大的时间变异性可能是由于静脉对脑区的贡献不同所致。信号了结果表明，灌注方法可以提供比基于BOLD的成像更准确的神经元活动时序信息。J.磁共振成像2005; 21：111 - 117.© 2005 Wiley利斯公司
PurposeTo compare the temporal behaviors of perfusion and blood oxygenation level‐dependent (BOLD) functional magnetic resonance imaging (fMRI) in the detection of timing differences between distinct brain areas, and determine potential latency differences between stimulus onset and measurable fMRI signal in sensory cortices.Materials and MethodsInversion recovery (IR) spin‐echo echo‐planar imaging (EPI) and T2*‐weighted gradient‐echo EPI sequences were used for perfusion‐ and BOLD‐weighted experiments, respectively. Simultaneous auditory and visual stimulations were employed in an event‐related (ER) paradigm. Signal time courses were averaged across 40 repeated trials to evaluate the onset of activation and to determine potential differences of activation latency between auditory and visual cortices and between these scanning methods.ResultsTemporal differences between visual and auditory areas ranged from 90–200 msec (root‐mean‐square (RMS) = 134 msec) and from –80 to 930 msec (RMS = 604 msec) in perfusion and BOLD measurements, respectively. The temporal variability detected with BOLD sequences was larger between subjects and was significantly greater than that in the perfusion response (P< 0.04). The measured time to half maximum (TTHM) values for perfusion imaging (visual, 3260 ± 710 msec; auditory, 3130 ± 700 msec) were earlier than those in BOLD responses (visual, 3770 ± 430 msec; auditory, 3360 ± 460 msec).ConclusionThe greater temporal variability between brain areas detected with BOLD could result from differences in the venous contributions to the signal. The results suggest that perfusion methods may provide more accurate timing information of neuronal activities than BOLD‐based imaging. J. Magn. Reson. Imaging 2005;21:111–117. © 2005 Wiley‐Liss, Inc.