Relationships Among Sleep Disturbance,Reward System Functioning,Anhedonia, and Depressive Symptoms

Recent models propose reward system dysfunction as a key mediator of the relationship between sleep and depression and anhedonia. This study explored interrelationships among sleep disturbance, depressive symptoms, anhedonia, and reward responsiveness. Two-hundred and sixty undergraduate students completed questionnaires and a daily diary paradigm assessing sleep, reward responsiveness, depression, anhedonia, and positive affect over 1 week. Baseline sleep disturbance was associated with depressive symptoms, anhedonia, and reward responsiveness. Daily diary sleep parameters showed differential associations with anticipatory versus consummatory reward responsiveness and positive affect. Poorer sleep quality, shorter sleep duration, and longer awakening after sleep onset predicted blunted anticipatory and consummatory reward responsiveness, while increased sleep onset latency and lower sleep efficiency predicted only decreased consummatory reward responsiveness. All sleep indices, except sleep onset latency, were associated with positive affect. Findings demonstrate unique associations between disparate sleep disturbance and reward responsiveness elements, highlighting new treatment mechanisms for anhedonia and depression.     

Role of Reward Sensitivity and Processing in Major Depressive and Bipolar Spectrum Disorders

Since Costello’s (1972) seminal Behavior Therapy article on loss of reinforcers or reinforcer effectiveness in depression, the role of reward sensitivity and processing in both depression and bipolar disorder has become a central area of investigation. In this article, we review the evidence for a model of reward sensitivity in mood disorders, with unipolar depression characterized by reward hyposensitivity and bipolar disorders by reward hypersensitivity. We address whether aberrant reward sensitivity and processing are correlates of, mood-independent traits of, vulnerabilities for, and/or predictors of the course of depression and bipolar spectrum disorders, covering evidence from self-report, behavioral, neurophysiological, and neural levels of analysis. We conclude that substantial evidence documents that blunted reward sensitivity and processing are involved in unipolar depression and heightened reward sensitivity and processing are characteristic of hypomania/mania. We further conclude that aberrant reward sensitivity has a trait component, but more research is needed to clearly demonstrate that reward hyposensitivity and hypersensitivity are vulnerabilities for depression and bipolar disorder, respectively. Moreover, additional research is needed to determine whether bipolar depression is similar to unipolar depression and characterized by reward hyposensitivity, or whether like bipolar hypomania/mania, it involves reward hypersensitivity.     

反馈相关负波：一种抑郁症的生物标记物

反馈相关负波(feedback-related negativity, FRN)是一种反映个体奖赏敏感性的脑电成分; 而抑郁症患者的特征之一是奖赏敏感性的减弱。大量横向研究发现了重度抑郁症患者(major depressive disorder, MDD)及有患抑郁症风险群体的FRN异常; 另外, 纵向研究发现FRN的异常能够预测青春期抑郁发作及抑郁症状发展, 压力、睡眠等因素在其中起调节作用。这提示FRN可能在对抑郁症的诊断及分型、抑郁高危群体的筛查及干预等方面具有潜在价值。目前关于FRN的心理功能依然存在一些争议, 在未来的研究中应该进一步明确FRN的功能和测量方法, 并探明抑郁症的异质性和共病对FRN的作用, 也应关注老年人群体中FRN与抑郁症的关系。     

Abnormal Neural Sensitivity to Monetary Gains Versus Losses Among Adolescents at Risk for Depression

Major depressive disorder aggregates within families, although the mechanisms of transfer across generations are not well understood. In light of converging biological and behavioral evidence that depressive symptoms are associated with impaired reward processing, we examined whether adolescent girls with a parental history of depression would also exhibit abnormal reward sensitivity. We performed a negative mood induction and then recorded the feedback negativity, a neural index of reward processing, while individuals completed a gambling task. High-risk adolescents reported greater sadness following the mood induction compared to low-risk adolescents. Among the high-risk group, sadness was strongly associated with a blunted feedback negativity, even after controlling for baseline mood and trait neuroticism. This suggests that high-risk adolescents are more reactive to negative stimuli, which significantly alter neural sensitivity to monetary gains and losses. The feedback negativity might be used to identify information processing abnormalities in high-risk populations prior to the onset of a major depressive episode.     

A Direct Method of Assessing Underlying Cognitive Risk for Adolescent Depression

An enduring tendency towards negative thinking is thought to increase vulnerability for future depression. However, it has not been possible to assess this tendency in non-depressed mood states. We examined if response latency to endorse dysfunctional attitudes is associated with depressive outcomes in a longitudinal study. A sample of young people at familial risk of depression (N?=?252, aged 10–19, 56.3 % female) completed a computer-administered dysfunctional attitude scale. The main outcome measure was the difference in reaction time to agree versus disagree with dysfunctional attitudes. Cross-sectional differences between current and previous depression and no psychiatric disorder groups as well as longitudinal associations with depressive symptoms were examined. Young people with current and previous depression were quicker to agree with dysfunctional attitudes than those without disorder. In young people free from depressive disorder, faster agreements with dysfunctional attitudes were specifically associated with increased depressive symptoms over time. Self-reported dysfunctional attitudes did not differentiate the formerly depressed and no disorder groups and showed a longitudinal association with depressive symptoms for older adolescents only. Reaction time to endorse dysfunctional attitudes may indicate changes in affective processing that represent an early risk for future depression that is not indexed by self-report measures of negative thought.     

Cognitive dysfunction in depression: neurocircuitry and new therapeutic strategies

Major depressive disorder (MDD) is a disabling medical condition associated with significant morbidity, mortality and public health costs. However, neurocircuitry abnormalities underlying depression remain incompletely understood and consequently current treatment options are unfortunately limited in efficacy. Recent research has begun to focus specifically on cognitive aspects of depression and potential neurobiological correlates. Two fundamental types of cognitive dysfunction observed in MDD are cognitive biases, which include distorted information processing or attentional allocation toward negative stimuli, and cognitive deficits, which include impairments in attention, short-term memory and executive functioning. In this article, we present a selective review of current research findings in these domains and examine neuroimaging research that is beginning to characterize the neurocircuitry underlying these biases and deficits. We propose that deficient cognitive functioning, attention biases and the sustained negative affect characteristic of MDD can be understood as arising in part from dysfunctional prefrontal-subcortical circuitry and related disturbances in the cognitive control of emotion. Finally, we highlight potential new pharmacological and non-pharmacological therapeutic strategies for MDD based on an evolving mechanistic understanding of the disorder.     

Sleep and psychopathology

This article examines the relationship between sleep disturbance and psychopathology. Epidemiological, cross-sectional, and longitudinal data suggest a high rate of comorbidity between sleep disturbance and psychopathology, particularly between insomnia, anxiety, and depression. Between 50% and 80% of psychiatric patients complain of sleep disturbances during the acute phase of their illness. Conversely, among treatment-seeking individuals with a primary complaint of insomnia and randomly selected community samples, approximately one third display a concurrent psychopathology, one third exhibit psychological symptoms that do not necessarily exceed the threshold for a psychiatric disorder, and another third present insomnia as a functionally autonomous disorder. There is a positive relationship between severity of sleep disturbances and concurrent psychopathology, but unequivocal evidence of a cause-and-effect relationship is still lacking. However, longitudinal data suggest that anxiety and stressful life events often precede acute sleep difficulties, whereas persistent insomnia may be a risk factor for subsequent development of depression. Implications for the prevention and treatment of coexisting sleep disturbance and psychopathology are discussed.     

Emotion Regulation Mediates the Relationship between ADHD and Depressive Symptoms in Youth

A significant literature suggests that youth diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD) are at increased risk for later depression relative to youth without ADHD. Youth with co-occurring ADHD and depression experience more serious impairments and worse developmental outcomes than those with either disorder alone, including increased rates of suicidal ideation and suicide completion. Despite these very serious outcomes, few studies have examined the mechanisms underlying the relationship between ADHD and depression in youth. The present study examined emotion regulation (ER) as a mediator of the relationship between ADHD and depressive symptoms in 69 youth between the ages of 10 and 14, with (n?=?37) and without (n?=?32) ADHD. Parent and youth ratings of depressive symptoms and ER were collected. Youth with ADHD reported significantly more depressive symptoms and poorer ER ability relative to youth without ADHD. ER fully mediated the relationship between ADHD and depressive symptoms. Limitations and clinical implications are discussed.     

Relationship between sleep disturbance,depression and anxiety in the 12 months following a cardiac event

We aimed to assess the prevalence of sleep disturbance in a cardiac patient population over a 12-month period and assess its relationship with treatment adherence, self-efficacy, anxiety and depression. A total of 134 patients consecutively admitted to two Australian hospitals after acute myocardial infarction (31%), or to undergo bypass surgery (29%) or percutaneous coronary intervention (40%) were interviewed at six weeks and four and 12 months. Sleep disturbance was measured using a recode of the Beck Depression Inventory (v.2) item 16. Anxiety and depression were assessed by the Hospital Anxiety and Depression Scale. Sleep disturbance was highly prevalent (69%) at 6 weeks but was not associated with 12-month psychological outcomes. Path analysis revealed that sleep disturbance at 4 months was, however, associated with reduced treatment adherence and self-efficacy, and higher anxiety and depression scores at 12 months. The high prevalence of sleep disturbance in this study and its association with psychological outcomes may have adverse prognostic implications and possibly impede cardiac rehabilitation efforts.     

Effects of task-relevant incentives on the electrophysiological correlates of error processing in major depressive disorder

Major depressive disorder (MDD) is associated with action-monitoring dysfunction—particularly, disrupted error processing. Whether such dysregulation is further modulated by task incentives is largely unknown. The goal of this study was to investigate possible dysfunctions in error processing in MDD as a function of varying task incentives and clinical profile. To this end, we recorded the error-related negativity (ERN) and error positivity (Pe) in 18 MDD participants and 18 healthy controls during a Stroop task that intermixed no-incentive and reward trials. Relative to controls, MDD participants showed (1) larger ERN irrespective of task incentives, and (2) reduced Pe during reward (but not no-incentive) trials. Moreover, among MDD participants, Pe amplitudes were negatively correlated with depression severity and clinical symptoms. The present findings highlight distinct effects of task incentives on electrophysiological components of error processing and are interpreted within current theories of action monitoring and incentive processing in depression.     

Could Treatment Matching Patients’ Beliefs About Depression Improve Outcomes?

Patients’ beliefs about depression and expectations for treatment can influence outcomes of major depressive disorder (MDD) treatments. We hypothesized that patients with weaker biological beliefs (less endorsement of [a] biochemical causes and [b] need for medication) and more optimistic treatment expectations (greater improvement and shorter time to improvement), have better outcomes in cognitive therapy (CT). Outpatients with recurrent MDD who received acute-phase CT (N = 152), and a subset of partial or unstable responders (N = 51) randomized to 8 months of continuation CT or fluoxetine with clinical management, completed repeated measures of beliefs, expectations, and depression. As hypothesized, patients with weaker biological beliefs about depression, and patients who expected a shorter time to improvement, experienced greater change in depressive symptoms and more frequent response to acute-phase CT. Moreover, responders who received continuation treatment better matched to their biological beliefs (i.e., responders with weaker biological beliefs about depression who received continuation CT, or responders with stronger biological beliefs about depression who received continuation fluoxetine) had fewer depressive symptoms and less relapse/recurrence by 32 months after acute-phase CT than did responders who received mismatched continuation treatment. Specific screening and/or intervention targeting patients’ biological beliefs about depression could increase CT efficacy.     

Sleep Quality and the Subjective Experience of Autobiographical Memory: Differential Associations by Memory Valence and Temporality

The primary goal of the present research was to examine associations between sleep quality and the subjective experience of autobiographical events. In an online study, 141 university students reported on past events that varied by valence (positive or negative) and temporality (most significant or from the previous 2 weeks); they also completed measures of sleep quality and depression. Relative to participants with good sleep quality, participants with poor sleep quality thought more about their negative experiences, reported negative events that occurred more frequently, and used more negative emotion words when describing recent negative events. In some instances, depressive symptoms mediated the relation between sleep quality and elements of autobiographical reports. Future experimental work should examine the directionality of these effects, with the ultimate goal of improving sleep quality, mental health, and the manner in which individuals discuss and make meaning of their negative life events. Copyright © 2017 John Wiley & Sons, Ltd.     

Functional connectomics in depression: insights into therapies

Depression is a common mental disorder characterized by heterogeneous cognitive and behavioral symptoms. The emerging research paradigm of functional connectomics has provided a quantitative theoretical framework and analytic tools for parsing variations in the organization and function of brain networks in depression. In this review, we first discuss recent progress in depression-associated functional connectome variations. We then discuss treatment-specific brain network outcomes in depression and propose a hypothetical model highlighting the advantages and uniqueness of each treatment in relation to the modulation of specific brain network connectivity and symptoms of depression. Finally, we look to the future promise of combining multiple treatment types in clinical practice, using multisite datasets and multimodal neuroimaging approaches, and identifying biological depression subtypes.     

青少年抑郁的快感缺失的神经机制研究

抑郁逐渐低龄化使得青少年抑郁备受关注。快感缺失,作为抑郁的一种核心临床症状,已成为抑郁最具前景的内表型之一。然而,青少年抑郁的快感缺失的神经机制迄今仍不清楚。本研究首先汇总两种神经机制模型即三元模型和社会挫折模型;其次,在多种奖励加工如金钱奖励、努力动机奖励、未来奖励和社会奖励条件下,概述青少年抑郁的快感缺失的神经机制前沿进展。未来可以深入探索努力动机奖励和未来奖励在预测青少年抑郁中的作用,加强研究青春期阶段与性别是如何交互影响早期抑郁快感缺失,将无创伤电磁刺激应用于青少年抑郁干预中,进一步澄清青少年抑郁的快感缺失的神经发展机制。     

Outcomes From the Transdiagnostic Sleep and Circadian Intervention (TranS-C) for Midlife and Older Adults With Serious Mental Illness and Sleep and Circadian Dysfunction

The present study tested outcomes of the Transdiagnostic Sleep and Circadian Intervention (TranS-C) among midlife and older adults with serious mental illness (SMI). Further, we tested predictors—credibility, expectancy, usefulness, and utilization—that may affect TranS-C outcomes. Midlife and older participants from a community setting (>49 years, 62.3% female, 37.7% African American or Black) with sleep and circadian problems and SMI were randomized to receive TranS-C plus usual care (TranS-C+UC, n = 27) or usual care followed by delayed treatment with TranS-C (UC-DT, n = 26). Immediate and delayed TranS-C data were combined to increase power (combined n = 52). Outcomes were assessed at pretreatment, posttreatment, and 6-month follow-up. Credibility and expectancy were assessed during the second session. Usefulness and utilization of TranS-C skills were assessed at posttreatment and 6-month follow-up. TranS-C+UC, relative to UC-DT, was associated with improvements in depression symptoms, sleep disturbance, overall sleep health, and select sleep/wake outcomes, though not all improvements were sustained at 6-month follow-up. Lower usefulness of TranS-C skills predicted more severe sleep disturbance at posttreatment and daytime sleep-related impairment at posttreatment and 6-month follow-up. Lower utilization predicted more severe psychiatric symptoms at posttreatment, sleep disturbance at posttreatment and 6-month follow-up, and overall impairment and daytime sleep-related impairment at 6-month follow-up. Higher credibility and expectancy predicted greater usefulness of TranS-C skills at posttreatment and 6-month follow-up and greater utilization at 6-month follow-up. Together, findings highlight benefits of TranS-C for midlife and older adults with SMI. However, boosting credibility, expectancy, utilization, and usefulness may meaningfully improve TranS-C outcomes.     

Training attention improves decision making in individuals with elevated self-reported depressive symptoms

Depression is often characterized by attentional biases toward negative items and away from positive items, which likely affects reward and punishment processing. Recent work has reported that training attention away from negative stimuli reduced this bias and reduced depressive symptoms. However, the effect of attention training on subsequent learning has yet to be explored. In the present study, participants were required to learn to maximize reward during decision making. Undergraduates with elevated self-reported depressive symptoms received attention training toward positive stimuli prior to performing the decision-making task (n = 20; active training). The active-training group was compared to two other groups: undergraduates with elevated self-reported depressive symptoms who received placebo training (n = 22; placebo training) and a control group with low levels of depressive symptoms (n = 33; nondepressive control). The placebo-training depressive group performed worse and switched between options more than did the nondepressive controls on the reward maximization task. However, depressives that received active training performed as well as the nondepressive controls. Computational modeling indicated that the placebo-trained group learned more from negative than from positive prediction errors, leading to more frequent switching. The nondepressive control and active-training depressive groups showed similar learning from positive and negative prediction errors, leading to less-frequent switching and better performance. Our results indicate that individuals with elevated depressive symptoms are impaired at reward maximization, but that the deficit can be improved with attention training toward positive stimuli.     

The effects of rumination and negative cognitive styles on depression: a mediation analysis

Research on cognitive models of depression has identified negative cognitive styles and rumination as risk factors for depression. The present study examined the hypothesis that rumination mediates the effect of negative cognitive styles on depression. Specifically, we evaluated the differential effects of two aspects of rumination, characterized by brooding and reflection, on the relationship between negative cognitive styles and level of depressive symptoms. A total of 115 college students and 38 patients suffering from depressive disorders completed a battery of questionnaires measuring levels of depressive symptoms, brooding, reflection, and negative cognitive styles. The results support the notion that there exist two distinct dimensions of rumination and that, of the two, it is brooding and not reflection that mediates the relationship between negative cognitive styles and depression and contributes to its negative outcomes.     

The self and depression: Four psychological theories and their potential neural correlates

We review theory and research pertaining to psychodynamic, social, humanistic, and ethological models of the self and depression and examine research into the neurobiological bases of the self and depression. We provide a narrative review of classic and recent empirical evidence pertaining to these four models of the relation of the self to depression as well as exemplar relevant neurobiological research. Evidence stemming from each of the four theories reviewed here shows a robust relationship between deficits in the sense of self and depressive symptoms, as well as increases in depressive symptoms over time. A smaller body of literature has linked one’s sense of self to onsets of depressive episodes. A growing body of literature has linked self-relevant variables to functioning in various prefrontal and cortical midline brain regions as well as emotion and reward processing brain regions which have in turn been linked to depression. Evidence has therefore converged across all four theories and confirmed that a deficit in one’s sense of self confers risk for depression and that there is substantial overlap in the brain areas associated with one’s sense of self and depression.     

Obstructive sleep apnea and depression

Is there an association between obstructive sleep apnea (OSA) and depression? OSA is a common breathing-related sleep disorder. There have been reports that depressive symptoms can be associated with this sleep disorder. A number of investigations have addressed this issue. Although some have found no correlation, most studies have concluded that there is an association between OSA and depressive symptoms. Other investigations have shown that depressive symptoms improve with treatment of OSA, and that untreated OSA may contribute to treatment resistance in some cases of mood disorders. Within the framework of current psychiatric diagnostic criteria, the depressive symptoms associated with OSA can be viewed as a combination of a mood disorder secondary to a primary medical condition and an adjustment disorder with depressed mood. The question of whether OSA causes depressive symptoms can perhaps be best answered by viewing OSA and depression as having certain symptoms that are common to both disorders.     

Dispositional mindfulness,insomnia, sleep quality and dysfunctional sleep beliefs in post-treatment cancer patients

Dispositional mindfulness, or the tendency to be more mindful in daily life, has been associated with better psychological functioning and reduced overall distress. This study investigated the degree to which dispositional mindfulness was associated with sleep disturbances in cancer patients with insomnia. Further, we examined whether levels of mindfulness moderated the relationship between stress levels, mood disturbance, insomnia severity, sleep quality and dysfunctional sleep beliefs. Participants (N = 111) were adults who had been previously treated for cancer and currently met diagnostic criteria for insomnia. Higher levels of acting with awareness, non-judging and non-reacting were associated with better sleep and psychological outcomes. Despite these significant associations, mindfulness facets did not significantly moderate the relationship between stress, mood and sleep outcomes. This negative finding raises the possibility that increased mindfulness may not act directly to improve psychological outcomes, but rather through a series of other cognitive and affective changes. Our results emphasize the importance of addressing mood symptoms and stress appraisals as predictors of sleep disturbance in cancer patients.