Trajectories of reward sensitivity and depression across adolescence

描述（由申请人提供）：人们越来越关注青春期奖励敏感性的变化；特别是，青春期似乎是一个对奖励更加敏感的时期。同时，青春期是抑郁症状显着增加的时期，而抑郁症的特点是对奖励的敏感性降低。当前的项目结合脑电图、功能神经成像 (fMRI)、行为和自我报告措施，将奖励敏感性作为一种潜在特征进行研究。同样，我们考虑对抑郁症状（例如父母和儿童报告）进行多重评估，以便抑郁症状也可以建模为潜在特征。目前的提案检查了大量（N = 300）女孩样本（年龄从 9 岁到 14 岁）的奖励敏感性和抑郁症；此外，该样本将在初次访问两年后进行检查，以便可以检查横截面和纵向关系。在我们的试点数据中，我们广泛关注与反馈相关的消极性 (FRN)，这是一种在头皮上观察到的皮层电反应，在反馈表明金钱损失与收益相比后约 300 毫秒出现明显的消极性。我们的工作表明，收益和损失之间的神经分化是由奖励相关的正电位驱动的，该电位是在基底神经节的腹侧纹状体中产生的，与奖励相关的神经回路有关。我们发现 FRN 与基于功能磁共振成像的纹状体对奖励反应的测量以及奖励敏感性的行为指标有关。此外，我们发现，在抑郁程度较高的成年人和青少年中，FRN 都会降低，并且最近发现，与奖励相关的大脑活动的减少可以预测青少年在两年内抑郁症状的变化。目前的提案将这项工作扩展到更大的纵向样本，并纳入了奖励敏感性、抑郁症状和青春期的多种衡量标准。我们将评估：a）在跨越青春期两个时间点（相隔 2 年）的大样本中，奖励敏感性的多种测量与抑郁症状之间的关系（目标 1）； b) 奖赏敏感性和抑郁症状的规范性发育增加，特别是作为青春期阶段的函数（目标 2）； c）随着时间的推移，奖励敏感性与抑郁症状之间的前瞻性关系，以及第一次评估时的奖励敏感性是否可以预测两年后抑郁症的变化（目标3）；最后，青春期的变化是否预示着奖赏敏感性与后来的抑郁症状之间存在更强的联系（目标 3）。还评估了许多次要目标（例如，抑郁症状而非焦虑症状的特异性；唾液睾酮作为青春期阶段标志物的效用；压力生活事件的作用）。的 本研究将为奖赏的发育神经生物学以及与抑郁个体差异和青春期抑郁风险相关的神经生物学变化的文献做出贡献。 公共健康相关性：我们采用时间序列设计研究了 300 名女性（9 至 14 岁）青春期阶段和奖赏敏感性变化（RS；使用行为、ERP、fMRI 和自我报告方法测量）和抑郁症状的作用，并评估低 RS 是否可以预测抑郁症。

DESCRIPTION (provided by applicant): There is increasing focus on changes in reward sensitivity that take place across adolescence; in particular, puberty appears to be a time characterized by increased sensitivity to rewards. At the same time, puberty is a time characterized by a significant increase in depressive symptoms, and depression is characterized by reductions in sensitivity to rewards. The current project examines reward sensitivity as a latent trait, capitalizing on a combination of EEG, functional neuroimaging (fMRI), behavioral, and self-report measures. Along the same lines, we consider multiple assessments of depressive symptoms (e.g., parent and child reports) so that depressive symptoms can also be modeled as a latent trait. The current proposal examines both reward sensitivity and depression in a large (N=300) sample of girls, ranging from 9 to 14 years of age; moreover, this sample will be examined two years after the initial visit, so that both cross-sectional and longitudinal relationships can be examined. In our pilot data, we have focused extensively on the feedback-related negativity (FRN), an electrocortical response observed at the scalp as an apparent negativity approximately 300 ms following feedback indicating monetary loss compared to gain. Our work suggests that the neural differentiation between gains and losses is being driven by a reward-related positive potential that is generated in the ventral striatum-part of the basal ganglia that has been implicated in reward-related neural circuits. We have found that the FRN relates to fMRI-based measures of striatal response to rewards, as well as behavioral metrics of reward sensitivity. Moreover, we have found that the FRN is reduced in both adults and adolescents who are more depressed-and have recently found that reduced reward-related brain activity can predict changes in depressive symptoms over the course of two years among adolescents. The current proposal extends this work into a much larger and longitudinal sample, and incorporates multiple measures of reward sensitivity, depressive symptoms, and puberty. We will assess: a) the relationship between multiple measures of reward sensitivity and depressive symptoms in a large sample that spans adolescence at two time points, separated by 2 years (Aim 1); b) normative developmental increases in both reward sensitivity and depressive symptoms, especially as a function of pubertal stage (Aim 2); c) prospective relations between reward sensitivity and depressive symptoms over time, and whether reward sensitivity at the first assessment can predict changes in depression two years later (Aim 3); finally, if pubertal changes predicts a stronger link between reward sensitivity and later depressive symptoms (Aim 3). A number of secondary aims are also evaluated (e.g., specificity to depressive symptoms and not anxious symptoms; utility of salivary testosterone as a marker of pubertal stage; role of stressful life events). The present study will contribute to the literature on the developmental neurobiology of reward, as well as the neurobiological changes related to individual differences in depression and risk for depression across adolescence. PUBLIC HEALTH RELEVANCE: We examine the role of pubertal stage and change on reward sensitivity (RS; measured using behavioral, ERP, fMRI, and self-report methods) and depressive symptoms among 300 females (aged 9 to 14) in a time-sequential design-and evaluate if low RS can predicts depression.