The Role of Effort Discounting in the Link between Insomnia and Depression

三分之二的抑郁症患者也被证明符合失眠的标准， 它的存在与不良的临床病程、对抑郁症治疗的更大抵抗力和 复发和自杀的风险增加。旨在确定共有的生物、心理和社会过程的研究 与抑郁症和失眠症相关的治疗工具是必要的，以减少这些 消极后果，并改善退伍军人的健康和生活质量。拟议的CDA-2目标是奖励 处理，特别是与奖励相关的努力的处理，作为这样一种共性。具有以下特征的个人 研究表明，抑郁症患者比非抑郁症患者更容易打折努力， 这意味着他们更有可能贬低需要付出更大努力才能获得的回报。有一些 初步证据表明，睡眠障碍可能会导致努力打折扣，但这一效果尚未得到测试 在有临床意义的失眠的成年人中，之前也没有关于努力折扣治疗抑郁症的研究 充分描述了参与者中失眠的严重程度和流行率。这份CDA-2旨在 评估与奖赏相关的努力的处理与失眠有多大关系。 这项研究将涉及132名年龄在18-55岁之间的退伍军人，他们代表了一系列抑郁症和 采用象限入路治疗失眠症状严重程度。这种方法将确保良好的分配 低失眠/低抑郁、高失眠/低抑郁、低失眠/高抑郁的退伍军人 高度失眠/高度抑郁严重程度的分析，利用连续的预测因素来最大化权力 并探讨失眠和抑郁对努力折扣的成分效应。退伍军人将参加 在为期一周的主观(睡眠日记)和客观(活动记录)睡眠评估中，随后进行评估 努力打折。努力折扣将通过奖励的努力支出和 累进比率任务，提供受试者愿意付出的努力的估计的行为测量 第四，为了金钱回报。为了评估失眠和奖赏处理之间关系的特异性， 退伍军人还将完成延迟折扣任务(奖励估值的衡量标准)，以及 反转学习任务(奖赏学习的衡量标准)。行为抑制/行为激活量表 惩罚敏感度/奖赏敏感度问卷是奖赏的自我报告测量 敏感度，也将进行管理。临床上患有严重失眠的退伍军人(即处于高位的退伍军人 失眠/低抑郁和高失眠/高抑郁组)将随机分配到认知组 失眠的行为疗法(CBT-I)或6周的等待控制期，之后他们将收到 CBT-I。将对睡眠和奖励处理进行治疗后/等待名单评估，以探索 失眠严重程度的变化是否与抑郁和努力折扣的变化有关。 失眠被假设为与更多的努力折扣有关(即，追求回报的努力减少)， 失眠的改善被认为与抑郁症的改善和 减少了工作折扣。因为对失眠/努力折扣关系的特殊性的评估是 作为探索性的，关于失眠对奖励评估或学习的影响，没有先验的假设。 CDA-2将为申请者提供翻译睡眠和心理健康方面的重点培训 研究(主要导师菲利普·格尔曼博士)、临床试验方法和高级统计(共同导师Dr。 奖励引导行为的评估和分析(共同导师Robin Nusslock博士)和 资质和专业发展(共同导师Steven Sayers博士)。这项研究的发现可能 加强退伍军人抑郁症和失眠治疗的临床实践指南。

Two-thirds of individuals with depression have also been shown to meet criteria for insomnia, the presence of which is associated with poor clinical course, greater resistance to depression treatment and an increased risk for relapse and suicidality. Research aimed at identifying the shared biopsychosocial processes relevant to both depression and insomnia is necessary to develop the therapeutic tools to reduce these negative outcomes and improve the health and quality of life of Veterans. The proposed CDA-2 targets reward processing, specifically the processing of reward-relevant effort, as one such commonality. Individuals with depression have been shown to engage more readily in effort discounting than non-depressed individuals, meaning that they are more likely to devalue rewards that require greater effort to obtain. There is some preliminary evidence that sleep disturbance may lead to effort discounting, but this effect has not been tested in adults with clinically significant insomnia, nor have previous studies of effort discounting in depression adequately characterized the severity and prevalence of insomnia among participants. This CDA-2 aims to evaluate the extent to which the processing of reward-relevant effort is meaningfully related to insomnia. The study will involve 132 Veterans ages 18 – 55 selected to represent a continuum of depression and insomnia symptom severity utilizing a quadrant approach. This approach will ensure a good distribution of Veterans with low insomnia/low depression, high insomnia/low depression, low insomnia/ high depression, and high insomnia/high depression severity for an analysis that utilizes continuous predictors to maximize power and explore the component effects of insomnia and depression on effort discounting. Veterans will participate in a week of subjective (sleep diary) and objective (actigraphy) assessments of sleep followed by assessments of effort discounting. Effort discounting will be measured with the Effort Expenditure for Rewards and the Progressive Ratio Tasks, behavioral measures that provide estimates of the effort subjects are willing to put forth for monetary rewards. To assess the specificity of the relationship of insomnia and reward processing, Veterans will also complete the delayed discounting task (a measure of reward valuation), and the probabilistic reversal learning task (a measure of reward learning). The Behavioral Inhibition/Behavioral Activation Scales and The Sensitivity to Punishment/Sensitivity to Reward Questionnaire are self-report measures of reward sensitivity and will also be administered. Veterans with clinically significant insomnia (i.e., Veterans in the high insomnia/low depression and high insomnia/high depression groups) will be randomly assigned to Cognitive Behavioral Therapy for Insomnia (CBT-I) or to a 6-week waitlist control period, after which they will receive CBT-I. Post-treatment/waitlist assessments of sleep and reward processing will be conducted to explore whether changes in insomnia severity are related to both changes in depression and effort discounting. Insomnia is hypothesized to be related to increased effort discounting (i.e., reduced effort to pursue rewards), and improvements in insomnia are hypothesized to be correlated with both improvements in depression and reduced effort discounting. As assessments of the specificity of the insomnia/effort discounting relationship are exploratory, there are no a priori hypotheses as to the effects of insomnia on reward valuation or learning. This CDA-2 will provide the applicant with focused training in translational sleep and mental health research (primary mentor Dr. Philip Gehrman), clinical trial methods and advanced statistics (co-mentor Dr. Michael Thase), assessment and analysis of reward guided behavior (co-mentor Dr. Robin Nusslock) and grantsmanship and professional development (co-mentor Dr. Steven Sayers). Findings from this study could enhance clinical practice guidelines for the treatment of Veterans with depression and insomnia.