Resting-state and event-related frontal alpha asymmetry have been suggested as potential neurobiological biomarkers for depression and other psychiatric conditions. To be used as such, sufficient test-retest reliability needs to be demonstrated. However, test-retest reliability is underinvestigated for event-related alpha asymmetry. The objective of this study was to examine both short-term within-session and long-term between-session reliability of stimulus-related medial and lateral frontal as well as parietal alpha EEG asymmetry in healthy subjects during a simple emotional face processing task. Twenty-three healthy adults participated in two sessions with a test-retest interval of about 1 week. Reliability was estimated with Pearson’s correlation coefficient and paired t test. Results revealed moderate to high within-session reliability of stimulus-related alpha asymmetry for all electrode sites and both conditions. Alpha asymmetry mean values did not change significantly within sessions. Between-session reliability was fair for frontomedial and moderate for frontolateral stimulus-related asymmetry. Exploratory exclusion of subjects with unstable between-session self-rating scores of emotional state and empathy toward stimuli resulted in some higher reliability values. Our results indicate that stimulus-related alpha asymmetry may serve as a useful electrophysiological tool given its adequate within-session reliability. However, long-term stability of stimulus-related frontal alpha asymmetry over 1 week was comparatively low and varied depending on electrode position. Influencing state factors during EEG recording, such as current mood or stimulus engagement, should be considered in future study designs and analyses. Further, we recommend to analyze alpha asymmetry from both frontomedial and frontolateral sites.
Neuropsychobiology

中文翻译：

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健康受试者呈现情绪面部刺激时额叶和顶叶 Alpha 不对称的重测可靠性

静息状态和事件相关的额叶 α 不对称已被认为是抑郁症和其他精神疾病的潜在神经生物学生物标志物。要如此使用，需要证明足够的重测信度。然而，对于与事件相关的 alpha 不对称性的重测信度研究不足。本研究的目的是在一个简单的情绪面部处理任务中检查健康受试者与刺激相关的内侧和外侧额叶以及顶叶 alpha EEG 不对称性的短期内和长期会话间可靠性。23 名健康成年人参加了两次测试，重新测试间隔约为 1 周。使用 Pearson 相关系数和配对t估计可靠性测试。结果显示，所有电极部位和两种情况下，与刺激相关的 alpha 不对称性的会话内可靠性都为中到高。阿尔法不对称平均值在会话内没有显着变化。会话间的可靠性对于额内侧来说是公平的，对于额外侧刺激相关的不对称性来说是中等的。探索性排除会话间情绪状态自评分数和对刺激的同情心不稳定的受试者会导致一些更高的可靠性值。我们的结果表明，与刺激相关的 alpha 不对称性可以作为一种有用的电生理工具，因为它具有足够的会话内可靠性。然而，刺激相关的额叶 α 不对称在 1 周内的长期稳定性相对较低，并且因电极位置而异。在未来的研究设计和分析中，应考虑影响 EEG 记录过程中的状态因素，例如当前情绪或刺激参与。此外，我们建议从额内侧和额外侧部位分析 alpha 不对称性。
神经心理生物学