Olfaction and Emotion in Depression: Behavioral Electrodermal and ERP Measures

描述(由申请人提供)： 考虑到涉及嗅觉、情绪和抑郁的皮质和皮质下(边缘)结构的重叠，嗅觉研究可能在阐明抑郁症患者与情绪反应异常和快感缺失相关的神经生理功能障碍方面具有特殊的前景。然而，关于抑郁症患者嗅觉功能的研究相对较少，现有的研究由于缺乏神经生理学措施和方法上的困难而受到限制。我们建议开发一个新的研究方向，其中将测量抑郁症患者和健康对照组对愉快和不愉快的嗅觉刺激的多通道事件相关脑电位(ERPs)。这将利用现有的精确控制嗅觉刺激的方法(嗅觉仪)，以及电生理领域的新数据分析技术。电流源密度(CSD；表面拉普拉斯)和时间主成分分析(PCA)相结合，得到对应于有意义的嗅觉ERP成分的径向电流源的无参考测量。此外，高浓度和低浓度的令人愉快和令人不快的气味将根据心理生理学测量来选择，这将允许单独评估情绪效价和强度影响。除了大脑的ERPs，通常伴随着情绪处理的双侧电皮肤活动(EDA)将被记录下来，以提供交感调节的自主神经对嗅觉刺激的唤醒措施。在初步的心理物理测量后，我们建议测试30名未服用药物的抑郁症患者和30名健康对照，这些患者在性别、年龄、利手、吸烟史和种族/种族方面匹配。在检测任务中，将获得高和低浓度的愉快和不愉快气味的ERP、EDA和行为测量，旨在最大限度地减少认知-评估过程。还将获得气味强度/价态的单独判断，以及用于评估气味检测阈值和气味识别的标准行为测试。将使用基于面试者的精神病理学和自我评级来检查患者的事件相关电位和行为嗅觉缺陷与快感缺乏和其他抑郁症状的关系。快感缺乏是严重抑郁症的主要诊断特征。增加对其神经生理学基础的了解可以改善对诊断亚型的识别，并为预测治疗反应提供新的标记物。对抑郁症患者嗅觉的研究应该为测量和理解情绪反应的异常提供一个新的窗口，例如在抑郁症中快乐体验的减少。这也可能导致诊断评估和治疗选择的新方法的发展。

DESCRIPTION (provided by applicant): Given the overlap of cortical and subcortical (limbic) structures involved in olfaction, emotion and depression, the study of olfaction may hold particular promise for elucidating neurophysiologic dysfunctions associated with abnormalities of emotional reactivity and anhedonia in depressed patients. There has, however, been relatively little study of olfactory function in depressed patients and existing studies have been limited by lack of neurophysiologic measures and methodological difficulties. We propose to develop a new direction of research, in which multichannel event-related brain potentials (ERPs) will be measured in depressed patients and healthy controls to pleasant and unpleasant olfactory stimuli. This will take advantage of existing methods for precise control of olfactory stimuli (olfactometer) and also new data analytic techniques in the electrophysiologic domain. Current source density (CSD; surface Laplacian) and temporal principal components analysis (PCA) are combined to yield reference-free measures of radial current sources corresponding to meaningful olfactory ERP components. Also, high and low concentrations of pleasant and unpleasant odors will be selected on the basis of psychophysiologic measurements, which will allow separate assessment of emotional valence and intensity effects. In addition to brain ERPs, bilateral electrodermal activity (EDA), which typically accompanies emotional processing, will be recorded to provide sympathetically- mediated measures of autonomic arousal to the olfactory stimuli. After preliminary psychophysical measurements, we propose to test 30 unmedicated depressed patients and 30 healthy controls matched for gender, age, handedness, smoking history, and ethnicity/race. ERP, EDA and behavioral measures will be obtained to high and low concentrations of pleasant and unpleasant odors during a detection task, which is designed to minimize cognitive-evaluative processing. Separate judgments of odor intensity/valence will also be obtained, along with standard behavioral tests for assessing odor detection thresholds and odor identification. Interviewer-based and self-ratings of psychopathology will be used to examine the relation of ERP and behavioral olfactory deficits in patients to anhedonia and other symptoms of depression. Anhedonia is a cardinal diagnostic feature of major depression. Increased understanding of its neurophysiologic basis could lead to improved identification of diagnostic subtypes and new markers for prediction of treatment response. The study of olfaction in depressed patients should provide a new window for measuring and understanding abnormalities of emotional reactivity, such as reduced experience of pleasure in depression. This could also lead to development of new methods for diagnostic assessment and treatment selection.