Perturbation of cortical activity elicits regional and age-dependent effects on unconstrained reaching behavior: a pilot study.
Perturbation of cortical activity elicits regional and age-dependent effects on unconstrained reaching behavior: a pilot study.
复制标题
皮质活动的扰动会对不受限制的触及行为产生区域和年龄依赖性影响：一项试点研究。
DOI：
10.1007/s00221-021-06228-z
复制
发表时间：
2021
影响因子：
2
通讯作者：
Wittenberg,GeorgeF
中科院分区：
文献类型：
--
作者：
Urbin,MA;Tian,Jing;Lafe,CharlesW;McKernan,GinaP;Kortzorg,Nick;Wyers,Lore;VanHalewyck,Florian;Boisgontier,MatthieuP;Levin,Oron;Swinnen,StephanP;Jonkers,Ilse;Wittenberg,GeorgeF
从运动前和辅助运动区域的贡献达到行为在老年人类还没有很好地理解。这些实验的目的是检查对特定皮层区域的扰动对年轻人和老年人控制无约束到达重力的影响。双脉冲经颅磁刺激（TMS）应用于针对初级运动皮质（M1）、背侧运动前区（PMA）、辅助运动区（SMA）或背外侧前额叶皮质（DLPFC）的头皮部位。刺激的目的是在视觉提示之前或之后干扰目标皮质区域正在进行的活动，以启动中等节奏的到达三个垂直目标位置之一。在河段的早期和后期，运动幅度均存在区域效应。PMA扰动对峰值速度前到达距离的影响大于其他区域。在PMA和M1相对于SMA和DLPFC的扰动下，在峰值速度前后，到达处与直线路径的偏差更大，总体曲率更大。扰动增加了到达路径在峰值速度时和峰值速度后经过时间的位置变异性。尽管扰动对年轻被试的触达影响更大，但该组在速度峰值时的触达路径变异性较小，此后调整运动轨迹所需的时间也较少。这些发现支持PMA在视觉引导下的作用，并提示感觉运动加工的年龄相关变化，可能是由于皮质抑制控制的丧失。
Contributions from premotor and supplementary motor areas to reaching behavior in aging humans are not well understood. The objective of these experiments was to examine effects of perturbations to specific cortical areas on the control of unconstrained reaches against gravity by younger and older adults. Double-pulse transcranial magnetic stimulation (TMS) was applied to scalp locations targeting primary motor cortex (M1), dorsal premotor area (PMA), supplementary motor area (SMA), or dorsolateral prefrontal cortex (DLPFC). Stimulation was intended to perturb ongoing activity in the targeted cortical region before or after a visual cue to initiate moderately paced reaches to one of three vertical target locations. Regional effects were observed in movement amplitude both early and late in the reach. Perturbation of PMA increased reach distance before the time of peak velocity to a greater extent than all other regions. Reaches showed greater deviation from a straight-line path around the time of peak velocity and greater overall curvature with perturbation of PMA and M1 relative to SMA and DLPFC. The perturbation increased positional variability of the reach path at the time of peak velocity and the time elapsing after peak velocity. Although perturbations had stronger effects on reaches by younger subjects, this group exhibited less reach path variability at the time of peak velocity and required less time to adjust the movement trajectory thereafter. These findings support the role of PMA in visually guided reaching and suggest an age-related change in sensorimotor processing, possibly due to a loss of cortical inhibitory control.