Alouit Anaëlle, Gavaret Martine, Ramdani Céline, Lindberg Påvel G, Dupin Lucile
Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Team "Stroke, from prognostic determinants and translational research to personalized interventions", 75014, Paris, France.
Université Paris Cité, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Team "Stroke, from prognostic determinants and translational research to personalized interventions", 75014, Paris, France; GHU-Paris Psychiatrie et Neurosciences, Hôpital Sainte Anne, Service de neurophysiologie clinique, F-75014, Paris, France.
Neuroimage. 2025 Jul 1;314:121249. doi: 10.1016/j.neuroimage.2025.121249. Epub 2025 May 4.
Somatosensory evoked potentials (SEPs) recorded with electroencephalography offer insights into cortical responses to tactile stimulation, typically elicited through temporally precise electrical stimulation. Although vibrotactile stimulation is more ecologically valid but less common, studies directly comparing EEG responses to both electrical and vibrotactile finger stimulation are limited. This study examines and compares (a) cortical responses, (b) connectivity patterns, and (c) somatotopic accuracy of these stimulation types on the fingers. In two experiments, SEPs were recorded from healthy participants' right-hand finger stimulation, using either electrical (experiment 1, n = 22) or vibrotactile (experiment 2, n = 22) stimulation. Vibrotactile stimuli were delivered at 10, 50, and 250 Hz, targeting different ranges of tactile mechanoreceptors activations. Electrical stimulation reliability was assessed across two days, showing consistent SEP amplitudes and latencies. Both stimulation types generated three early components (P1, N1, P2), but all vibrotactile components were increasingly delayed compared to electrical stimulation. Vibrotactile stimulation exhibited stronger localized connectivity in early components (P1, N1) in the left hemisphere, while electrical stimulation showed broader connectivity at P2. Electrical stimulation provided a clearer somatotopic organization in the postcentral gyrus than vibrotactile stimulation. These findings suggest distinct processing for electrical versus vibrotactile finger stimulation. These two stimulation methods are not interchangeable in somatosensory studies: the temporal shift in vibrotactile responses reflects selective activation of Pacinian corpuscles, whereas electrical stimulation yields stronger generalized cortical processing. Electrical stimulation may engage a serial processing pathway starting in the primary somatosensory cortex, while vibrotactile stimulation could involve parallel processing in both primary and secondary somatosensory cortices.
通过脑电图记录的体感诱发电位（SEP）能深入了解皮层对触觉刺激的反应，这种刺激通常通过时间精确的电刺激引发。尽管振动触觉刺激在生态学上更具有效性，但使用较少，直接比较脑电图对电刺激和振动触觉手指刺激反应的研究有限。本研究考察并比较了（a）皮层反应、（b）连接模式以及（c）这些刺激类型在手指上的躯体定位准确性。在两个实验中，从健康参与者右手手指刺激记录SEP，实验1（n = 22）使用电刺激，实验2（n = 22）使用振动触觉刺激。振动触觉刺激以10、50和250赫兹的频率施加，针对不同范围的触觉机械感受器激活。在两天内评估电刺激的可靠性，结果显示SEP振幅和潜伏期一致。两种刺激类型均产生三个早期成分（P1、N1、P2），但与电刺激相比，所有振动触觉成分的延迟都越来越明显。振动触觉刺激在左半球早期成分（P1、N1）中表现出更强的局部连接性，而电刺激在P2时显示出更广泛的连接性。与振动触觉刺激相比，电刺激在中央后回提供了更清晰的躯体定位组织。这些发现表明电刺激与振动触觉手指刺激的处理方式不同。在体感研究中，这两种刺激方法不可互换：振动触觉反应的时间偏移反映了帕西尼小体的选择性激活，而电刺激产生更强的广义皮层处理。电刺激可能参与从初级体感皮层开始的串行处理通路，而振动触觉刺激可能涉及初级和次级体感皮层的并行处理。
