Table 1_Role of right dorsolateral prefrontal cortex–left primary motor cortex interaction in motor inhibition in Parkinson’s disease.docx

BackgroundImpaired motor inhibition in Parkinson’s disease (PD) is associated with functional alterations in the frontal-basal ganglia (BG) neural circuits. The right dorsolateral prefrontal cortex (DLPFC), pre-supplementary motor area (pre-SMA), and primary motor cortex (M1) play key roles in regulating this inhibition. However, the changes in interhemispheric interactions during motor inhibition in PD have not been clearly defined.
MethodsWe used dual-site paired-pulse transcranial magnetic stimulation (ppTMS) to examine the interactions between the right DLPFC and pre-SMA and the left M1 in 30 patients with early-stage PD and 30 age-matched healthy controls (HC) during both resting and active conditions, specifically while performing a stop-signal task (SST).
ResultsStop-signal reaction times (SSRT) were significantly longer in PD patients compared to HC. The right DLPFC–left M1 interaction, at both short- and long-latency intervals, showed enhanced inhibition in PD following the stop-signal. In PD patients, SSRT was correlated with the inhibition of the right DLPFC–left M1 interaction, with stronger inhibition associated with shorter SSRT.
ConclusionThe deficit in reactive inhibition observed in PD is linked to an abnormal modulation of the right DLPFC–left M1 interaction during the stopping process.

背景：帕金森病（Parkinson’s disease, PD）患者的运动抑制功能受损，与额-基底神经节（frontal-basal ganglia, BG）神经环路的功能异常密切相关。右侧背外侧前额叶皮层（right dorsolateral prefrontal cortex, DLPFC）、前辅助运动区（pre-supplementary motor area, pre-SMA）及初级运动皮层（primary motor cortex, M1）在调控该类抑制过程中发挥关键作用。然而，帕金森病患者运动抑制阶段的半球间交互变化尚未得到明确阐明。
方法：本研究采用双位点配对脉冲经颅磁刺激（dual-site paired-pulse transcranial magnetic stimulation, ppTMS），在静息与任务执行状态下（具体为完成停止信号任务（stop-signal task, SST）时），对30例早期帕金森病患者及30名年龄匹配的健康对照者（healthy controls, HC）的右侧DLPFC与pre-SMA、左侧M1之间的交互作用进行检测。
结果：帕金森病患者的停止信号反应时（stop-signal reaction times, SSRT）显著长于健康对照者。在停止信号触发后，帕金森病患者的右侧DLPFC-左侧M1交互作用在短、长潜伏期下均表现出增强的抑制效应。在帕金森病患者群体中，SSRT与右侧DLPFC-左侧M1交互的抑制程度呈显著相关：抑制效应越强，SSRT越短。
结论：本研究观察到的帕金森病患者反应性抑制缺陷，与停止动作过程中右侧DLPFC-左侧M1交互的异常调控存在紧密关联。