Bonzano Laura, Biggio Monica, Brigadoi Sabrina, Pedullà Ludovico, Pagliai Monica, Iester Costanza, Brichetto Giampaolo, Cutini Simone, Bove Marco
Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; IRCCS Ospedale Policlinico San Martino, Genoa, Italy.
Department of Experimental Medicine, Section of Human Physiology, University of Genoa, Genoa, Italy.
Neuroimage. 2023 Oct 15;280:120348. doi: 10.1016/j.neuroimage.2023.120348. Epub 2023 Aug 24.
Manual dexterity is referred to as the skill to perform fine motor movements and it has been assumed to be associated to the cognitive domain, as well as the sensorimotor one. In this work, we investigated with functional near-infrared spectroscopy the cortical activations elicited by the execution of the 9-HPT, i.e., a standard test evaluating manual dexterity in which nine pegs were taken, placed into and then removed from nine holes on a board as quickly as possible. For comparison, we proposed a new active control task mainly involving the sensorimotor domain, in which the pegs must be placed and removed using the same single hole (1-HPT). Behaviorally, we found two distinct groups based on the difference between the execution time of the 9-HPT and the 1-HPT (ΔHPT). Cortical areas belonging to the network controlling reaching and grasping movements were active in both groups; however, participants showing a large ΔHPT presented significantly higher activation in prefrontal cortical areas (right BA10 and BA11) during 9-HPT and 1-HPT performance with respect to the participants with a small ΔHPT, who showed a deactivation in BA10. Unexpectedly, we observed a significant linear relationship between ΔHPT and right BA10 activity. This suggested that participants performing the 9-HPT more slowly than the 1-HPT recruited prefrontal areas implicitly exploiting the cognitive skills of planning, perhaps in search of a motor strategy to solve the test activating attentional and cognitive control processes, but this resulted not efficient and instead increased the time to accomplish a manual dexterity task.
手部灵巧性是指执行精细运动的技能，人们一直认为它与认知领域以及感觉运动领域相关。在这项研究中，我们使用功能近红外光谱技术研究了执行9孔插板试验（9-HPT）所引发的皮层激活情况，9-HPT是一项评估手部灵巧性的标准测试，要求尽可能快地拿起九个小钉，放入并随后从板上的九个孔中取出。为了进行比较，我们提出了一项主要涉及感觉运动领域的新主动控制任务，即使用同一个单孔（1-HPT）来放置和取出小钉。在行为学方面，我们根据9-HPT和1-HPT的执行时间差异（ΔHPT）发现了两个不同的组。在两组中，属于控制伸手和抓握运动网络的皮层区域均被激活；然而，与ΔHPT较小且在BA10区域表现为失活的参与者相比，ΔHPT较大的参与者在执行9-HPT和1-HPT任务时前额叶皮层区域（右侧BA10和BA11）的激活程度明显更高。出乎意料的是，我们观察到ΔHPT与右侧BA10的活动之间存在显著的线性关系。这表明，执行9-HPT比1-HPT慢的参与者会隐含地利用计划的认知技能来调用前额叶区域，可能是在寻找一种运动策略来完成测试，从而激活注意力和认知控制过程，但这并未产生高效的结果，反而增加了完成手部灵巧性任务的时间。
