Yamamoto Tetsuya, Sugaya Nagisa, Siegle Greg J, Kumano Hiroaki, Shimada Hironori, Machado Sergio, Murillo-Rodriguez Eric, Rocha Nuno B, Nardi Antonio E, Takamura Masahiro, Okamoto Yasumasa, Yamawaki Shigeto
Graduate School of Technology, Industrial and Social Sciences, Tokushima University, Tokushima, Japan.
Unit of Public Health and Preventive Medicine, School of Medicine, Yokohama City University, Yokohama, Japan.
Front Psychiatry. 2018 Dec 12;9:691. doi: 10.3389/fpsyt.2018.00691. eCollection 2018.
The neurophysiological mechanisms of cognitive reactivity, the primary vulnerability factor of major depressive disorder (MDD) recurrence, remain unclear in individuals with recovered MDD (rMDD). Because gamma-band responses (GBRs) can be used to measure cognitive processing, they may also be useful for elucidating the mechanisms underlying cognitive reactivity. Identifying these mechanisms may permit the development of an index for predicting and preempting MDD recurrence. Here, to identify the neurophysiological mechanisms of cognitive reactivity, we examined the characteristics of the GBRs evoked/induced by emotional words in participants with and without rMDD after inducing a negative mood. Thirty-three healthy control participants and 18 participants with rMDD completed a lexical emotion identification task during electroencephalography along with assessments of cognitive reactivity after negative mood induction. No between-group differences were identified for the task reaction times; however, the rMDD group had significantly higher cognitive reactivity scores than did the control group. Furthermore, the power of late GBRs to positive words was significantly greater in the rMDD group, with the greater power of late GBRs being related to higher cognitive reactivity. Considering the population studied, our findings cannot be completely generalized to populations other than adolescents, people with rMDD, and those without a history of co-morbid disorders and early life stress. Our findings indicate that the dysfunction of neural circuits related to higher-order processes like memory and attention might underlie cognitive reactivity. Altered late GBRs to positive information may be persistent biomarkers of the depression recurrence risk.
认知反应性是重度抑郁症（MDD）复发的主要脆弱性因素，在MDD康复个体（rMDD）中，其神经生理机制仍不清楚。由于伽马波段反应（GBRs）可用于测量认知加工，它们可能也有助于阐明认知反应性背后的机制。识别这些机制可能有助于开发一种预测和预防MDD复发的指标。在此，为了识别认知反应性的神经生理机制，我们在诱导负面情绪后，检查了有或无rMDD的参与者中由情感词汇诱发/诱导的GBRs特征。33名健康对照参与者和18名rMDD参与者在脑电图记录期间完成了一项词汇情感识别任务，并在负面情绪诱导后进行了认知反应性评估。任务反应时间未发现组间差异；然而，rMDD组的认知反应性得分显著高于对照组。此外，rMDD组中晚期GBRs对积极词汇的功率显著更大，晚期GBRs的更大功率与更高的认知反应性相关。考虑到所研究的人群，我们的研究结果不能完全推广到青少年、rMDD患者以及没有共病障碍和早期生活压力史的人群之外。我们的研究结果表明，与记忆和注意力等高阶过程相关的神经回路功能障碍可能是认知反应性的基础。对积极信息的晚期GBRs改变可能是抑郁症复发风险的持续生物标志物。
