Nishida Keiichiro, Minami Shota, Yamane Tomonari, Ueda Satsuki, Tsukuda Banri, Ikeda Shunichiro, Haruna Daisuke, Yoshimura Masafumi, Kanazawa Tetsufumi, Koenig Thomas
Department of Neuropsychiatry, Osaka Medical and Pharmaceutical University, Osaka, Japan.
Department of Neuropsychiatry, Kansai Medical University, Osaka, Japan.
Brain Behav. 2025 May;15(5):e70580. doi: 10.1002/brb3.70580.
Microstate analysis involves examining the temporal dynamics of electroencephalogram (EEG) signals and serves as a crucial method for exploring the neural basis of psychiatric disorders. This study investigates the effects of transcranial direct current stimulation (tDCS) on specific microstate parameter maps-D and C in patients with depression, specifically targeting the dorsomedial prefrontal cortex (DMPFC) and left dorsolateral prefrontal cortex (DLPFC).
We conducted an open-label, between-subject, crossover trial involving 19 patients clinically diagnosed with depression. A 1 mA electrical current was administered, with anodal stimulation specifically targeting the DMPFC or the left DLPFC. Microstate maps were derived from resting-state EEG recordings obtained prior to and following the application of tDCS. The EEG data were categorized into five distinct microstate classes for subsequent analysis.
The findings revealed a significant increase in the duration of microstate class D following stimulation in both groups, while microstate class C exhibited no notable changes. Additionally, a significant association was identified between the transition from microstate D to C and alterations in the State-Trait Anxiety Inventory-State (STAI-S) scores after left DLPFC stimulation.
Microstate map D appears to be associated with psychiatric disorders and executive functions, whereas map C may relate to the salience network and mind-wandering. Our findings suggest that microstate maps D and C are responsive to tDCS stimuli, indicating their potential as objective tools for anxiety assessment. Employing transition-focused parameters in EEG microstate analysis may enhance the tracking of rapidly fluctuating emotional states, rather than relying solely on duration metrics. Furthermore, the integration of non-invasive brain stimulation techniques, such as tDCS, with EEG microstate analysis holds significant promise for elucidating the neural mechanisms involved in depression.
UMIN-CTR Clinical Trial: UMIN000015046.
微状态分析涉及检查脑电图（EEG）信号的时间动态，是探索精神疾病神经基础的关键方法。本研究调查经颅直流电刺激（tDCS）对抑郁症患者特定微状态参数图D和C的影响，具体针对背内侧前额叶皮质（DMPFC）和左侧背外侧前额叶皮质（DLPFC）。
我们进行了一项开放标签、受试者间交叉试验，纳入19例临床诊断为抑郁症的患者。施加1 mA电流，阳极刺激具体针对DMPFC或左侧DLPFC。微状态图源自tDCS应用前后获得的静息态EEG记录。EEG数据被分为五个不同的微状态类别用于后续分析。
结果显示，两组刺激后微状态类别D的持续时间显著增加，而微状态类别C无明显变化。此外，在左侧DLPFC刺激后，从微状态D到C的转变与状态-特质焦虑量表-状态（STAI-S）评分的变化之间存在显著关联。
微状态图D似乎与精神疾病和执行功能相关，而图C可能与突显网络和走神有关。我们的研究结果表明，微状态图D和C对tDCS刺激有反应，表明它们作为焦虑评估客观工具的潜力。在EEG微状态分析中采用以转变为重点的参数可能会增强对快速波动情绪状态的追踪，而不是仅依赖持续时间指标。此外，将tDCS等非侵入性脑刺激技术与EEG微状态分析相结合，对于阐明抑郁症涉及的神经机制具有重要前景。
UMIN-CTR临床试验：UMIN000015046。
