Department of Neuroscience & Padova Neuroscience Center, University of Padua, Padua, Italy; Brain Imaging and Neural Dynamics Research Group, IRCCS, San Camillo Hospital, Venice Italy.
Section of Rehabilitation Department of Neuroscience, University of Padua, Padua, Italy; Padova Neuroscience Center, University of Padua, Padua, Italy.
Neuroimage. 2021 Feb 15;227:117655. doi: 10.1016/j.neuroimage.2020.117655. Epub 2020 Dec 15.
Different cortical regions respond with distinct rhythmic patterns of neural oscillations to Transcranial Magnetic Stimulation (TMS). We investigated natural frequencies induced by TMS in left and right homologous dorsolateral prefrontal cortices (DLPFC) and related hemispheric differences. In 12 healthy young adults, single-pulse TMS was delivered in different blocks close to F3 and F4 channels to target left and right DLPFC. An occipital site near PO3 was stimulated as control. TMS-related spectral perturbation analyses were performed on recorded EEG data. A widespread unspecific increase in theta power was observed for all stimulation sites. However, occipital TMS induced greater alpha activity and a 10.58 Hz natural frequency, while TMS over the left and right DLPFC resulted in similar beta band modulations and a natural frequency of 18.77 and 18.5 Hz, respectively. In particular, TMS-related specific increase in beta activity was stronger for the right than the left DLPFC. The right DLPFC is more specifically tuned to its natural beta frequency when it is directly stimulated by TMS than with TMS over the left counterpart (or a posterior region), while the left DLPFC increases its beta activity more similarly irrespective of whether it is directly stimulated or through right homologous stimulation. These results yield important implications for both basic neuroscience research on inter-hemispheric prefrontal interactions and clinical applications.
不同的皮质区域对经颅磁刺激（TMS）会产生不同的神经振荡节律模式。我们研究了 TMS 在左、右侧同源背外侧前额叶皮质（DLPFC）中诱导的自然频率及其相关的半球差异。在 12 名健康年轻成年人中，在接近 F3 和 F4 通道的不同位置给予单脉冲 TMS，以靶向左、右侧 DLPFC。以枕部 PO3 附近的刺激作为对照。对记录的 EEG 数据进行 TMS 相关的频谱扰动分析。观察到所有刺激部位的θ功率都出现了广泛的非特异性增加。然而，枕部 TMS 引起了更大的α活动和 10.58 Hz 的自然频率，而左、右侧 DLPFC 的 TMS 则导致类似的β频带调制和 18.77 Hz 和 18.5 Hz 的自然频率，分别。特别是，右侧 DLPFC 的 TMS 相关β活动增加比左侧 DLPFC 更强。当右侧 DLPFC 直接受到 TMS 刺激时，其对自然β频率的调谐比通过 TMS 对左侧对应区域（或后区域）的调谐更为特异性，而左侧 DLPFC 增加其β活动的方式更为相似，无论是否直接受到刺激或通过右侧同源刺激。这些结果对涉及半球间前额叶相互作用的基础神经科学研究和临床应用都具有重要意义。
