Coleman Sarah L, Sharpley Christopher F, Vessey Kirstan A, Evans Ian D, Williams Rebecca J, Bitsika Vicki
Brain-Behaviour Research Group, University of New England, Armidale, NSW, 2351, Australia.
Rev Neurosci. 2025 May 5. doi: 10.1515/revneuro-2025-0023.
Depression remains one of the most common and debilitating neuropsychiatric conditions, with little consistency in treatment efficacy. Some of the lack of success in developing effective treatments has been the absence of a reliable biomarker of depression, despite many attempts. One such potential biomarker is the electrical activity of the brain that occurs in the gamma band (30-200 Hz). To evaluate the state of research into gamma as a biomarker of depression, a review of recent research literature was conducted. A total of 31 relevant papers was identified, 22 of which used resting-state studies, and nine included a stimulus-task. These studies were examined here in terms of their definition of gamma, sample sizes, research focus, brain region examined, and EEG methodologies used. Due to the range of methodologies, some inconsistent results emerged but several valuable findings remained, including that depressed patients usually had higher gamma power than their healthy controls (HC), that the imposition of a perceptual task into the research protocol also introduced a strong element of confound to the results, and that studies that sought to evaluate the role of gamma in treatment were yet to be established as reliable. Key issues for future research are discussed, and the potential for gamma as a biomarker of depression is evaluated as emerging.
抑郁症仍然是最常见且使人衰弱的神经精神疾病之一，治疗效果缺乏一致性。尽管进行了许多尝试，但在开发有效治疗方法方面缺乏成功的部分原因是缺乏可靠的抑郁症生物标志物。一种这样的潜在生物标志物是大脑在伽马波段（30 - 200赫兹）出现的电活动。为了评估将伽马作为抑郁症生物标志物的研究现状，对最近的研究文献进行了综述。总共确定了31篇相关论文，其中22篇使用静息状态研究，9篇包括刺激任务。在此从伽马的定义、样本量、研究重点、检查的脑区以及使用的脑电图方法等方面对这些研究进行了审视。由于方法的多样性，出现了一些不一致的结果，但仍有一些有价值的发现，包括抑郁症患者通常比健康对照（HC）具有更高的伽马功率，在研究方案中引入感知任务也给结果带来了很强的混杂因素，以及试图评估伽马在治疗中的作用的研究尚未被确立为可靠的。讨论了未来研究的关键问题，并评估了伽马作为抑郁症生物标志物的潜力正在显现。
