Ageing changes effective connectivity of motor networks during bimanual finger coordination
Ageing changes effective connectivity of motor networks during bimanual finger coordination
复制标题
DOI：
10.1016/j.neuroimage.2016.09.014
复制
发表时间：
2016-12-01
期刊：
影响因子：
5.7
通讯作者：
Timmermann, Lars
中科院分区：
文献类型：
--
作者：
Loehrer, Philipp Alexander;Nettersheim, Felix Sebastian;Timmermann, Lars
双手手指的协调能力随着年龄的增长而下降。然而，对于导致这种衰退的运动系统的神经生理学改变知之甚少。在本研究中，我们使用 128 通道脑电图 (EEG) 来评估皮质、运动相关大脑区域的因果相互作用。惯用右手的年轻和老年受试者执行复杂的时间和空间耦合以及时间耦合和空间非耦合的手指敲击。采用动态因果模型（DCM）进行诱导反应，我们推断出任务诱导的核心运动网络内的有效连接，该网络包括双侧初级运动皮层（M1）、外侧前运动皮层（1PM）、辅助运动区（SMA）和前额叶皮层（PFC）。行为分析显示，老年受试者的错误率和执行时间显着增加，证实运动功能随着年龄的增长而下降。此外，DCM 分析表明，这种与年龄相关的衰退可能与半球间和前额叶到前运动连接的特定改变有关。年轻和老年受试者在进行时间和空间耦合运动时表现出抑制性的左向右 M1-M1 耦合。当运动在空间上分离时，衰老对半球间连接的影响尤其明显。在这里，老年参与者仍然表达抑制性的左向右 M1-M1 耦合，而年轻人中不存在这种联系。此外，衰老影响前额叶到运动前的连接。在所有情况下，老年受试者都表现出从左 PFC 到左下午 1 点的显着耦合。相比之下，年轻参与者表现出左侧PFC与SMA的连接。这些结果表明，（i）在空间不耦合的运动中，半球间MI连接随着年龄的增长而增加，并且（ii）支持这样的观点，即衰老与侧前额叶到前运动耦合（PFC到IPM）的增强以及优势半球内内侧通路（PFC到SMA）的低激活有关。 (C) 2016 Elsevier Inc. 保留所有权利。
Bimanual finger coordination declines with age. However, relatively little is known about the neurophysiological alterations in the motor-system causing this decline. In the present study, we used 128 channel electroencephalography (EEG) to evaluate causal interactions of cortical, motor-related brain areas. Right-handed young and elderly subjects performed complex temporally and spatially coupled as well as temporally coupled and spatially uncoupled finger tappings. Employing dynamic causal modelling (DCM) for induced responses, we inferred task-induced effective connectivity within a core motor network comprising bilateral primary motor cortex (M1), lateral premotor cortex (1PM), supplementary motor area (SMA), and prefrontal cortex (PFC).Behavioural analysis showed significantly increased error rates and performance times for elderly subjects, confirming that motor functions decrease with ageing. Additionally, DCM analysis revealed that this age-related decline can be associated with specific alterations of interhemispheric and prefrontal to premotor connectivity. Young and elderly subjects exhibited inhibitory left to right M1-M1 coupling during performance of temporally and spatially coupled movements. Effects of ageing on interhemispheric connectivity particularly emerged when movements became spatially uncoupled. Here, elderly participants still expressed inhibitory left to right M1-M1 coupling, whereas no such connection was present in the young. Furthermore, ageing affected prefrontal to premotor connectivity. In all conditions, elderly subjects showed significant couplings from left PFC to left 1PM. In contrast, young participants exhibited left PFC to SMA connections.These results demonstrate that (i) in spatially uncoupled movements interhemispheric MI-connectivity increases with age and (ii) support the idea that ageing is associated with enhanced lateral prefrontal to premotor coupling (PFC to IPM) and hypoactivation of a medial pathway (PFC to SMA) within the dominant hemisphere. (C) 2016 Elsevier Inc. All rights reserved.