Balance perturbation-evoked cortical N1 responses are larger when stepping and not influenced by motor planning.
Balance perturbation-evoked cortical N1 responses are larger when stepping and not influenced by motor planning.
复制标题
平衡扰动引起的皮质 N1 反应在迈步时更大，并且不受运动规划的影响。
DOI：
10.1152/jn.00341.2020
复制
发表时间：
2020
影响因子：
2.5
通讯作者：
Ting,LenaH
中科院分区：
文献类型：
--
作者：
Payne,AidenM;Ting,LenaH
在自动平衡校正肌肉活动的同时，在脑电图记录中观察到皮质N1对平衡扰动的反应。我们最近观察到较大的皮质N1的个人谁有更大的困难，抵制补偿步骤，这表明N1可能会受到步进或反应策略的变化。在这里，我们测试皮层N1反应是否受到步进（计划步骤与脚到位）或事先计划（计划与计划外步骤）的影响。我们假设，事先规划的步骤将减少皮层N1的平衡扰动的反应幅度。在19名健康的年轻人（年龄19-38岁; 8名男性和11名女性），我们测量了48个向后平移的支持面扰动不可预测的时间和幅度在一个单一的实验会话诱发的皮层N1振幅。参与者被要求计划对一半扰动的步进反应，但要抵制步进否则。扰动包括一个简单的（8厘米，16厘米/秒）扰动，这是相同的参与者，并没有自然地引起补偿步骤，和高度调整困难（18-22厘米，38-42厘米/秒）扰动，经常引起补偿步骤，尽管指示抵制步进。与我们的假设相反，皮层N1反应幅度之间没有不同的计划和计划外的步进反应，但皮层的反应是11%以上的执行计划的补偿步骤相比，nonstepping反应困难的扰动。这些结果表明一个可能的作用，皮层N1在执行补偿步骤平衡恢复，这种作用是不受影响的补偿步骤是否被计划前perturbation.NEW & NOTEWORTHThe皮层N1平衡扰动的反应较大时，执行补偿步骤，这表明皮层N1和随后的运动行为之间的关系。此外，皮层N1响应不受步进反应的事先规划的影响，这表明运动结果的可预测性不会以与扰动刺激的可预测性相同的方式影响N1。
The cortical N1 response to balance perturbation is observed in electroencephalography recordings simultaneous to automatic balance-correcting muscle activity. We recently observed larger cortical N1s in individuals who had greater difficulty resisting compensatory steps, suggesting the N1 may be influenced by stepping or changes in response strategy. Here, we test whether the cortical N1 response is influenced by stepping (planned steps versus feet-in-place) or prior planning (planned vs. unplanned steps). We hypothesized that prior planning of a step would reduce the amplitude of the cortical N1 response to balance perturbations. In 19 healthy young adults (ages 19–38; 8 men and 11 women), we measured the cortical N1 amplitude evoked by 48 backward translational support-surface perturbations of unpredictable timing and amplitude in a single experimental session. Participants were asked to plan a stepping reaction on half of perturbations, but to resist stepping otherwise. Perturbations included an easy (8 cm, 16 cm/s) perturbation that was identical across participants and did not naturally elicit compensatory steps, and a height-adjusted difficult (18–22 cm, 38–42 cm/s) perturbation that frequently elicited compensatory steps despite instructions to resist stepping. In contrast to our hypothesis, cortical N1 response amplitudes did not differ between planned and unplanned stepping reactions, but cortical responses were 11% larger with the execution of planned compensatory steps compared with nonstepping responses to difficult perturbations. These results suggest a possible role for the cortical N1 in the execution of compensatory steps for balance recovery, and this role is not influenced by whether the compensatory step was planned before the perturbation.NEW & NOTEWORTHYThe cortical N1 response to balance perturbation is larger when executing compensatory steps, suggesting a relationship between the cortical N1 and subsequent motor behavior. Additionally, the cortical N1 response is not impacted by prior planning of the stepping reaction, suggesting that predictability of the motor outcome does not impact the N1 in the same way as predictability of the perturbation stimulus.