Wang Wenjie, Liu Yuan, Wang Guoyao, Cheng Qian, Ming Dong
Academy of Medical Engineering and Translational Medicine, Tianjin University, Weijin Road Nankai District, Tianjin, China.
Haihe Laboratory of Brain-computer Interaction and Human-machine Integration, Tianjin, China.
Cereb Cortex. 2024 Sep 3;34(9). doi: 10.1093/cercor/bhae277.
Fine sensory modalities play an essential role in perceiving the world. However, little is known about how the cortico-cortical distinguishes between dynamic and static tactile signals. This study investigated oscillatory connectivity during a tactile discrimination task of dynamic and static stimulation via electroencephalogram (EEG) recordings and the fast oscillatory networks across widespread cortical regions. While undergoing EEG recordings, the subject felt an electro-tactile presented by a 3-dot array. Each block consisted of 3 forms of stimulation: Spatio-temporal (dynamic), Spatial (static), and Control condition (lack of electrical stimulation). The average event-related potential for the Spatial and Spatio-temporal conditions exhibited statistically significant differences between 25 and 75, 81 and 121, 174 and 204 and 459 and 489 ms after stimulus onset. Based on those times, the sLORETA approach was used to reconstruct the inverse solutions of EEG. Source localization appeared superior parietal at around 25 to 75 ms, in the primary motor cortex at 81 to 121 ms, in the central prefrontal cortex at 174 to 204 and 459 to 489 ms. To better assess spectral brain functional connectivity, we selected frequency ranges with correspondingly significant differences: for static tactile stimulation, these are concentrated in the Theta, Alpha, and Gamma bands, whereas for dynamic stimulation, the relative energy change bands are focused on the Theta and Alpha bands. These nodes' functional connectivity analysis (phase lag index) showed 3 distinct distributed networks. A tactile information discrimination network linked the Occipital lobe, Prefrontal lobe, and Postcentral gyrus. A tactile feedback network linked the Prefrontal lobe, Postcentral gyrus, and Temporal lobe. A dominant motor feedforward loop network linked the Parietal cortex, Prefrontal lobe, Frontal lobe, and Parietal cortex. Processing dynamic and static tactile signals involves discriminating tactile information, motion planning, and cognitive decision processing.
精细感觉模态在感知世界中起着至关重要的作用。然而，关于皮质-皮质如何区分动态和静态触觉信号，我们知之甚少。本研究通过脑电图（EEG）记录以及广泛皮质区域的快速振荡网络，调查了动态和静态刺激的触觉辨别任务期间的振荡连接性。在进行EEG记录时，受试者感受到由三点阵列呈现的电触觉。每个块由三种刺激形式组成：时空（动态）、空间（静态）和对照条件（无电刺激）。空间和时空条件下的平均事件相关电位在刺激开始后25至75、81至121、174至204以及459至489毫秒之间表现出统计学上的显著差异。基于这些时间，使用sLORETA方法重建EEG的逆解。源定位在约25至75毫秒时出现在顶上叶，81至121毫秒时在初级运动皮层，174至204以及459至489毫秒时在中央前额叶皮层。为了更好地评估频谱脑功能连接性，我们选择了具有相应显著差异的频率范围：对于静态触觉刺激，这些集中在θ、α和γ波段，而对于动态刺激，相对能量变化波段集中在θ和α波段。这些节点的功能连接性分析（相位滞后指数）显示出三个不同的分布式网络。一个触觉信息辨别网络连接枕叶、前额叶和中央后回。一个触觉反馈网络连接前额叶、中央后回和颞叶。一个主要的运动前馈环路网络连接顶叶皮层、前额叶、额叶和顶叶皮层。处理动态和静态触觉信号涉及辨别触觉信息、运动规划和认知决策处理。
