Wriessnegger Selina C, Kirchmeyr Daniela, Bauernfeind Günther, Müller-Putz Gernot R
Institute of Neural Engineering, Graz University of Technology, Stremayrgasse 16/IV, 8010 Graz, Austria.
Institute of Neural Engineering, Graz University of Technology, Stremayrgasse 16/IV, 8010 Graz, Austria.
Brain Cogn. 2017 Oct;117:108-116. doi: 10.1016/j.bandc.2017.06.010. Epub 2017 Jun 30.
We examined force related hemodynamic changes during the performance of a motor execution (ME) and motor imagery (MI) task by means of multichannel functional near infrared spectroscopy (fNIRS). The hemodynamic responses of fourteen healthy participants were measured while they performed a hand grip execution or imagery task with low and high grip forces. We found an overall higher increase of [oxy-Hb] concentration changes during ME for both grip forces but with a delayed peak maximum for the lower grip force. During the MI task with lower grip force, the [oxy-Hb] level increases are stronger compared to the MI with higher grip force. The facilitation in performing MI with higher grip strength might thus indicate less inhibition of the actual motor act which could also explain the later increase onset of [oxy-Hb] in the ME task with the lower grip force. Our results suggest that execution and imagery of a hand grip task with high and low grip forces, leads to different cortical activation patterns. Since impaired control of grip forces during object manipulation in particular is one aspect of fine motor control deficits after stroke, our study will contribute to future rehabilitation programs enhancing patient's grip force control.
我们通过多通道功能近红外光谱（fNIRS）检查了在执行运动执行（ME）和运动想象（MI）任务期间与力相关的血流动力学变化。在十四名健康参与者执行低握力和高握力的手握执行或想象任务时，测量了他们的血流动力学反应。我们发现，对于两种握力，在ME期间[氧合血红蛋白（oxy-Hb）]浓度变化的总体增加更高，但较低握力时峰值最大值出现延迟。在较低握力的MI任务期间，与较高握力的MI相比，[oxy-Hb]水平的增加更强。因此，以较高握力执行MI时的促进作用可能表明对实际运动行为的抑制较少，这也可以解释在较低握力的ME任务中[oxy-Hb]后期增加的起始时间。我们的结果表明，高握力和低握力的手握任务的执行和想象会导致不同的皮质激活模式。由于在中风后精细运动控制缺陷的一个方面特别是在物体操作期间握力控制受损，我们的研究将有助于未来的康复计划，以增强患者的握力控制。
