Oscillatory motor network activity during rest and movement: an fNIRS study.
Oscillatory motor network activity during rest and movement: an fNIRS study.
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DOI：
10.3389/fnsys.2014.00013
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发表时间：
2014
影响因子：
3
通讯作者：
Dhamala M
中科院分区：
文献类型：
--
作者：
Bajaj S;Drake D;Butler AJ;Dhamala M
在休息和任务条件下，通常会在大脑中观察到连接分布式大脑区域的相干网络振荡（<0.1 Hz）。存在什么振荡网络以及从休息到明确任务时网络振荡在连接强度、频率和方向上如何变化是最近研究的主题。在这里，我们利用功能性近红外光谱（fNIRS）测量的血流动力学活动来研究身体健全的个体感觉运动区域内的网络振荡。使用谱相关性方法，我们检查了辅助运动区（SMA）、左前运动皮层（LPMC）和左初级运动皮层（LM1）在扩展静息状态（RS）和任务间静息状态（btRS）期间如何绑定为网络，以及当参与者执行左手、右手和双侧手（LH、RH和BH）手指运动时网络的活动如何变化。我们发现：(i) 在 RS 期间，功率、相干性和格兰杰因果关系 (GC) 谱在频段 (0.01–0.04 Hz) 内有显着峰值，而在 btRS 和手指移动任务期间，峰值转移到更高的频率范围 (0.04–0.08 Hz)，(ii) RS 期间所有节点之间存在显着的双向连接，btRS 期间从 LM1 到 SMA 和 LM1 到 LPMC 的单向连接，以及(iii) 相对于 btRS，从 SMA 到 LM1 以及从 LPMC 到 LM1 的连接在 LH、RH 和 BH 手指运动中受到显着调节。在实际任务之前从 SMA 到 LM1 的单向连接在 LH 和 BH 手指移动期间更改为双向连接。单向性可能与运动抑制相关，而双向性可能与准备、感觉运动更新和受控执行相关。这些结果强调 fNIRS 是监测大脑活动光谱特征的有效工具，这可以作为监测脑损伤后恢复进展之前的重要前兆。
Coherent network oscillations (<0.1 Hz) linking distributed brain regions are commonly observed in the brain during both rest and task conditions. What oscillatory network exists and how network oscillations change in connectivity strength, frequency and direction when going from rest to explicit task are topics of recent inquiry. Here, we study network oscillations within the sensorimotor regions of able-bodied individuals using hemodynamic activity as measured by functional near-infrared spectroscopy (fNIRS). Using spectral interdependency methods, we examined how the supplementary motor area (SMA), the left premotor cortex (LPMC) and the left primary motor cortex (LM1) are bound as a network during extended resting state (RS) and between-tasks resting state (btRS), and how the activity of the network changes as participants execute left, right, and bilateral hand (LH, RH, and BH) finger movements. We found: (i) power, coherence and Granger causality (GC) spectra had significant peaks within the frequency band (0.01–0.04 Hz) during RS whereas the peaks shifted to a bit higher frequency range (0.04–0.08 Hz) during btRS and finger movement tasks, (ii) there was significant bidirectional connectivity between all the nodes during RS and unidirectional connectivity from the LM1 to SMA and LM1 to LPMC during btRS, and (iii) the connections from SMA to LM1 and from LPMC to LM1 were significantly modulated in LH, RH, and BH finger movements relative to btRS. The unidirectional connectivity from SMA to LM1 just before the actual task changed to the bidirectional connectivity during LH and BH finger movement. The uni-directionality could be associated with movement suppression and the bi-directionality with preparation, sensorimotor update and controlled execution. These results underscore that fNIRS is an effective tool for monitoring spectral signatures of brain activity, which may serve as an important precursor before monitoring the recovery progress following brain injury.