Background People with Parkinson’s disease (PD) have difficulties generating quick and accurate steps in anticipation of and/or in response to environmental hazards. However, neural mechanisms underlying performance in cognitively demanding stepping tasks are unclear. Objective This study compared activation patterns in cognitive and motor cortical regions using functional near-infrared spectroscopy (fNIRS) between people with PD and age-matched healthy older adults (HOA) during stepping tasks. Methods Fifty-two people with PD and 95 HOA performed a simple choice stepping reaction time test (CSRT) and 2 cognitively demanding stepping tests (inhibitory CSRT [iCSRT] and Stroop stepping test [SST]) on a computerized step mat. Cortical activation in the dorsolateral prefrontal cortex (DLPFC), Broca’s area, supplementary motor area (SMA), and premotor cortex (PMC) were recorded using fNIRS. Stepping performance and cortical activity were contrasted between groups and between the CSRT and the iCSRT and SST. Results The PD group performed worse than the HOA in all 3 stepping tests. A consistent pattern of interactions indicated differential hemodynamic responses between the groups. Compared with the CSRT, the PD group exhibited reduced DLPFC activity in the iCSRT and reduced SMA and PMC activity in the SST. The HOA exhibited increased DLPFC, SMA, and PMC activity when performing the SST in comparison with the CSRT task. Conclusions In contrast to the HOA, the PD group demonstrated reduced cortical activity in the DLPFC, SMA, and PMC during the more complex stepping tasks requiring inhibitory control. This may reflect subcortical and/or multiple pathway damage with subsequent deficient use of cognitive and motor resources.

中文翻译：

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帕金森病患者在执行需要抑制控制的复杂步进任务时表现出认知和运动皮层活动减少

背景 患有帕金森氏病 (PD) 的人在预测和/或应对环境危害时难以生成快速准确的步骤。然而，在认知要求高的步进任务中表现的神经机制尚不清楚。目的 本研究使用功能性近红外光谱 (fNIRS) 在 PD 和年龄匹配的健康老年人 (HOA) 之间在踏步任务中比较认知和运动皮层区域的激活模式。方法 52 名患有 PD 和 95 HOA 的人在计算机化的踏步垫上进行了一项简单的选择踏步反应时间测试 (CSRT) 和 2 项认知要求高的踏步测试（抑制性 CSRT [iCSRT] 和 Stroop 踏步测试 [SST]）。背外侧前额叶皮层 (DLPFC)、布洛卡区、辅助运动区 (SMA) 的皮层激活，和前运动皮层 (PMC) 使用 fNIRS 记录。各组之间以及 CSRT 与 iCSRT 和 SST 之间的踏步性能和皮层活动进行了对比。结果 PD 组在所有 3 个步进测试中的表现都比 HOA 差。一致的相互作用模式表明各组之间存在不同的血流动力学反应。与 CSRT 相比，PD 组在 iCSRT 中表现出降低的 DLPFC 活性，在 SST 中表现出降低的 SMA 和 PMC 活性。与 CSRT 任务相比，在执行 SST 时，HOA 表现出增加的 DLPFC、SMA 和 PMC 活动。结论 与 HOA 相比，PD 组在需要抑制控制的更复杂的步进任务期间表现出 DLPFC、SMA 和 PMC 的皮质活动降低。