Institut de Neurosciences de la Timone, Unité Mixte de Recherche 7289, Centre National de la Recherche Scientifique/Aix Marseille Université, 13385 Marseille Cedex 5, France.
Département de Kinanthropologie, Faculté des Sciences de l'activité Physique, Université de Sherbrooke, Sherbrooke, Québec J1H 5N4, Canada, and.
J Neurosci. 2020 Mar 18;40(12):2498-2509. doi: 10.1523/JNEUROSCI.1862-19.2020. Epub 2020 Feb 7.
Previous research suggests that so-called implicit and explicit processes of motor adaptation are implemented by distinct neural structures. Here we tested whether implicit sensorimotor adaptation and strategic re-aiming used to reduce movement error are reflected by spatially distinct EEG oscillatory components. We analyzed beta-band oscillations (∼13-30 Hz), which have long been linked to sensorimotor functions, at the time when these adaptive processes intervene for movement planning. We hypothesized that beta-band activity within sensorimotor regions relates to implicit adaptive processes, whereas beta-band activity within medial motor areas reflects deliberate re-aiming. In female and male human volunteers, we recorded EEG in a motor adaptation task in which a visual rotation was introduced in short series of trials separated by unperturbed trials. Participants were instructed in advance about the nature of the visual perturbation and trained to counter it by strategically re-aiming at a neighboring target. Consistent with our hypothesis, we found that preparatory beta-band activities within the two regions exhibited different patterns of modulation. Beta power in lateral central regions was attenuated when a change in the visual condition rendered internal-model predictions uncertain. In contrast, beta power in medial frontal regions was selectively decreased when participants strategically re-aimed their reaches. We propose that the reduction in lateral central beta power reflects an increased weighting of peripheral sensory information implicitly triggered when an adaptive change in the sensorimotor mapping is required, whereas the reduction in medial frontal beta-band activity relates to the inhibition of automatic motor responses in favor of cognitively controlled movements. Behavioral and modeling studies have proposed that so-called implicit and explicit components of motor adaptation recruit different neural circuits. Here, we investigated whether these different processes are reflected by spatially distinct beta-band activities. Analyzing EEG signals at the time they influence movement planning, during the foreperiod, we found that beta power within lateral central regions was decreased when a change in visual conditions required implicit sensorimotor remapping, which may reflect enhanced sensory processing when internal-model predictions are rendered uncertain. In contrast, beta-band power within medial frontal areas was selectively attenuated when participants deliberately re-aimed their movements to improve task performance, which may be associated with the inhibition of automatic motor responses in favor of cognitively controlled movements.
先前的研究表明，所谓的运动适应的内隐和外显过程是由不同的神经结构实现的。在这里，我们测试了内隐感觉运动适应和用于减少运动误差的策略性重新瞄准是否反映在空间上不同的 EEG 振荡成分中。我们分析了β波段振荡（约 13-30 Hz），长期以来与感觉运动功能相关，此时这些自适应过程会干预运动计划。我们假设，感觉运动区域内的β波段活动与内隐适应性过程有关，而内侧运动区域内的β波段活动反映了有意的重新瞄准。在女性和男性志愿者中，我们在一项运动适应任务中记录了 EEG，该任务在短系列试验中引入了视觉旋转，这些试验被未受干扰的试验隔开。参与者事先被告知视觉干扰的性质，并通过策略性地瞄准相邻目标来进行重新瞄准以进行训练。与我们的假设一致，我们发现两个区域内的预备性β波段活动表现出不同的调制模式。当视觉条件的变化使内部模型预测变得不确定时，外侧中央区域的β功率会降低。相比之下，当参与者策略性地重新瞄准他们的动作时，内侧额部区域的β功率会选择性地降低。我们提出，外侧中央β功率的降低反映了当需要对感觉运动映射进行适应性改变时，隐式触发的外围感觉信息的权重增加，而内侧额部β波段活动的降低与自动运动反应的抑制有关，有利于认知控制的运动。行为和建模研究已经提出，运动适应的所谓内隐和外显成分招募不同的神经回路。在这里，我们研究了这些不同的过程是否通过空间上不同的β波段活动来反映。在 Foreperiod 期间分析它们影响运动计划的时间的 EEG 信号时，我们发现当视觉条件的变化需要内隐的感觉运动重新映射时，外侧中央区域内的β功率会降低，这可能反映了当内部模型预测变得不确定时，增强了感觉处理。相比之下，当参与者故意重新瞄准动作以提高任务表现时，内侧额部区域内的β波段功率会选择性地降低，这可能与自动运动反应的抑制有关，有利于认知控制的运动。
