Özçoban Mehmet Akif, Tan Oğuz
Electronic and Automation Department, Naci Topcuoglu Vocational School, Gaziantep University, Gaziantep, Türkiye.
Feneryolu Medical Center, Üsküdar University, Istanbul, Türkiye.
Front Psychiatry. 2025 Jan 13;15:1480228. doi: 10.3389/fpsyt.2024.1480228. eCollection 2024.
Major Depressive Disorder (MDD) leads to dysfunction and impairment in neurological structures and cognitive functions. Despite extensive research, the pathophysiological mechanisms and effects of MDD on the brain remain unclear. This study aims to assess the impact of MDD on brain activity using EEG power spectral analysis and asymmetry metrics.
EEG recordings were obtained from 48 patients with MDD and 78 healthy controls. The data were segmented into 2-second windows (1024 data points) and analyzed using the Welch method, an advanced variant of the Fast Fourier Transform (FFT). A Hanning time window with 50% overlap was applied to compute the modified periodogram. Absolute and relative power, along with asymmetry values in the theta, alpha, and beta frequency bands, were calculated.
Patients with MDD exhibited significantly higher absolute and relative power in the theta and beta bands and decreased power in the alpha band compared to healthy controls. Asymmetry analysis revealed significant differences between symmetric channels in the theta band (F7-F8, C3-C4, T3-T4, T5-T6), alpha band (F7-F8, C3-C4, T3-T4, T5-T6, O1-O2), and beta band (C3-C4, T3-T4, T5-T6, P3-P4).
The findings suggest that MDD affects brain mechanisms and cognitive functions, as evidenced by altered power values in the theta and alpha bands. Additionally, asymmetry values in theta, alpha, and beta bands may serve as potential biomarkers for MDD. This study highlights that beyond the commonly used alpha asymmetry, theta and beta asymmetry can also provide valuable insights into the neurophysiological effects of MDD, aligning with previous neuroimaging studies that indicate impairments in memory, attention, and neuroanatomical connectivity in MDD.
重度抑郁症（MDD）会导致神经结构和认知功能的功能障碍及损害。尽管进行了广泛研究，但MDD对大脑的病理生理机制和影响仍不清楚。本研究旨在使用脑电图功率谱分析和不对称性指标评估MDD对大脑活动的影响。
从48例MDD患者和78名健康对照者获取脑电图记录。数据被分割为2秒的窗口（1024个数据点），并使用快速傅里叶变换（FFT）的高级变体——韦尔奇方法进行分析。应用具有50%重叠的汉宁时间窗口来计算修正周期图。计算绝对和相对功率，以及θ、α和β频段的不对称值。
与健康对照者相比，MDD患者在θ和β频段表现出显著更高的绝对和相对功率，而α频段功率降低。不对称性分析显示，在θ频段（F7 - F8、C3 - C4、T3 - T4、T5 - T6）、α频段（F7 - F8、C3 - C4、T3 - T4、T5 - T6、O1 - O2）和β频段（C3 - C4、T3 - T4、T5 - T6、P3 - P4）的对称通道之间存在显著差异。
研究结果表明，MDD会影响大脑机制和认知功能，θ和α频段功率值的改变证明了这一点。此外，θ、α和β频段的不对称值可能作为MDD的潜在生物标志物。本研究强调，除了常用的α不对称性之外，θ和β不对称性也可以为MDD的神经生理效应提供有价值的见解，这与先前的神经影像学研究一致，这些研究表明MDD患者存在记忆、注意力和神经解剖连接方面的损害。
