Vecchio Fabrizio, Alù Francesca, Orticoni Alessandro, Miraglia Francesca, Judica Elda, Cotelli Maria, Rossini Paolo Maria
Brain Connectivity Laboratory, Department of Neuroscience and Neurorehabilitation, IRCCS San Raffaele Roma, Via Val Cannuta, 247, 00166 Rome, Italy.
eCampus University, Novedrate, Como, Italy.
Cogn Neurodyn. 2022 Apr;16(2):297-308. doi: 10.1007/s11571-021-09713-x. Epub 2021 Sep 11.
Brain state in the time preceding the task affects motor performance at single trial level. Aim of the study was to investigate, through a single trial analysis of the Power Spectral Density (PSD) of the cortical sources of EEG rhythms, whether there are EEG markers, which can predict trial-by-trial the subject's performance as measured by the reaction time (RT). 20 healthy adult volunteers performed a specific visuomotor task while continuously recorded with a 64 electrodes EEG. For each single trial, the PSD of the cortical sources of EEG rhythms was obtained from EEG data to cortical current density time series in 12 regions of interest at Brodmann areas level. Results showed a statistically significant increase of posterior and limbic alpha 1 and of frontal beta 2 power, and a reduction of frontal and limbic delta and of temporal alpha 1 power, during triggering stimulus presentation for better performance, namely faster responses. At single trial level, correlation analyses between RTs and significant PSD, revealed positive correlations in frontal delta, temporal alpha 1, and limbic delta bands, and negative ones in frontal beta 2, parietal alpha 1, and occipital alpha 1 bands. Furthermore, the subject's faster responses have been found as correlated with the similarity between the PSD values in parietal and occipital alpha 1. Predicting individual's performance at single trial level, might be extremely useful in the clinical context, since it could allow to launch rehabilitative therapies in the most efficient brain state, avoiding useless interventions.
任务前的脑状态会在单次试验水平上影响运动表现。本研究的目的是通过对脑电图（EEG）节律的皮质源功率谱密度（PSD）进行单次试验分析，探究是否存在EEG标记物，能够逐次试验地预测以反应时间（RT）衡量的受试者表现。20名健康成年志愿者执行一项特定的视觉运动任务，同时用64电极脑电图持续记录。对于每个单次试验，从EEG数据中获取EEG节律的皮质源PSD，以得到布罗德曼区域水平上12个感兴趣区域的皮质电流密度时间序列。结果显示，在触发刺激呈现期间，为了获得更好的表现，即更快的反应，后顶叶和边缘α1以及额叶β2功率在统计学上显著增加，而额叶和边缘δ以及颞叶α1功率降低。在单次试验水平上，RT与显著PSD之间的相关性分析显示，额叶δ、颞叶α1和边缘δ频段存在正相关，而额叶β2、顶叶α1和枕叶α1频段存在负相关。此外，还发现受试者更快的反应与顶叶和枕叶α1中PSD值之间的相似性相关。在单次试验水平上预测个体表现，在临床环境中可能极其有用，因为它可以在最有效的脑状态下开展康复治疗，避免无效干预。
