NEURAL SUBSTRATES OF MEMORY SENSITIVITY FOR NEGATIVE STIMULI IN DEPRESSION

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。背景：抑郁症是一种广泛诊断和高度衰弱的疾病。抑郁的认知理论认为抑郁个体具有偏向于加工消极情感信息的认知偏差。与重性抑郁症相关的信息处理偏差通常是对负面信息的记忆敏感性增加，而对正面材料的记忆敏感性通常降低。重要的是，杏仁核与情绪化材料的编码和记忆有关，并且已经发现在抑郁症中表现出静息状态活动的升高。本研究的主要目的是评估杏仁核激活在与抑郁症相关的负性记忆偏差中的作用。 方法和结果：在没有其他Axis-I障碍的情况下，10名符合重度抑郁障碍标准的参与者和10名年龄和性别匹配的健康对照参与者作为本研究的参与者。功能磁共振成像（fMRI）被用来测量神经激活过程中的介绍和情感评价的积极，中性和消极的图片。扫描后一周，参与者参与了一项扫描仪外识别记忆任务，在此期间，他们被展示了他们在扫描仪中看到的图片和从未见过的图片，并被要求对每张图片的熟悉程度进行评级。抑郁症患者对负面图片的记忆敏感度显著高于对照组;两组参与者对正面图片的记忆敏感度没有差异。与这一发现相对应的是，抑郁症患者在对随后记忆的负面图片进行编码时，左杏仁核的活动显著高于对照组，但在对中性或正面图片进行编码时，活动并不显著。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Background: Depression is a widely diagnosed and highly debilitating disorder. Cognitive theories of depression posit that depressed individuals are characterized by cognitive biases favoring in the processing of negative affective information. An information-processing bias frequently associated with major depression is increased memory sensitivity for negative information and, often, decreased memory sensitivity for positive material. Importantly, the amygdala has been centrally implicated in encoding and memory for emotionally valenced material and has been found to show elevated resting state activity in depression. The primary goal of this study is to assess the role of amygdalar activation in the negative memory bias associated with depression. Methods and Results: Ten participants meeting criteria for major depressive disorder in the absence of other Axis-I disorders and ten age and sex-matched healthy control participants served as participants in this study. Functional magnetic resonance imaging (fMRI) was used to measure neural activation during presentation and affective evaluation of positive, neutral and negative pictures. One week following scanning, participants engaged in an out-of-scanner recognition memory task during which they were presented with pictures that they saw in the scanner and with never-seen pictures, and were asked to rate the familiarity of each picture. Memory sensitivity for negative pictures was significantly higher in depressed than in control participants; the two groups of participants did not differ in memory sensitivity for positive pictures. Corresponding to this finding, activity in the left amygdala was significantly higher during encoding of subsequently remembered negative pictures in depressed than in control participants, but not during encoding of neutral or positive pictures.