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Major Depressive Disorder (MDD) is characterized by rumination. Prior research suggests that resting-state brain activation reflects rumination when depressed individuals are not task engaged. However, no study has directly tested this. Here we investigated whether resting-state epochs differ from induced ruminative states for healthy and depressed individuals. Most previous research on resting-state networks comes from seed-based analyses with the posterior cingulate cortex (PCC). By contrast, we examined resting state connectivity by using the complete multivariate connectivity profile (i.e., connections across all brain nodes) and by comparing these results to seeded analyses. We find that unconstrained resting-state intervals differ from active rumination states in strength of connectivity and that overall connectivity was higher for healthy vs. depressed individuals. Relationships between connectivity and subjective mood (i.e., behavior) were strongly observed during induced rumination epochs. Furthermore, connectivity patterns that related to subjective mood were strikingly different for MDD and healthy control (HC) groups suggesting different mood regulation mechanisms., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: The benefits of expressive writing have been well documented among several populations, but particularly among those who report feelings of dysphoria. It is not known, however, if those diagnosed with Major Depressive Disorder (MDD) would also benefit from expressive writing., Methods: Forty people diagnosed with current MDD by the Structured Clinical Interview for DSM-IV participated in the study. On day 1 of testing, participants completed a series of questionnaires and cognitive tasks. Participants were then randomly assigned to either an expressive writing condition in which they wrote for 20 min over three consecutive days about their deepest thoughts and feelings surrounding an emotional event (n=20), or to a control condition (n=20) in which they wrote about non-emotional daily events each day. On day 5 of testing, participants completed another series of questionnaires and cognitive measures. These measures were repeated again 4 weeks later., Results: People diagnosed with MDD in the expressive writing condition showed significant decreases in depression scores (Beck Depression Inventory and Patient Health Questionnaire-9 scores) immediately after the experimental manipulation (Day 5). These benefits persisted at the 4-week follow-up., Limitations: Self-selected sample., Conclusions: This is the first study to demonstrate the efficacy of expressive writing among people formally diagnosed with current MDD. These data suggest that expressive writing may be a useful supplement to existing interventions for depression., (© 2013 Elsevier B.V. All rights reserved.)

Background: This study aimed to explore whether walking in nature may be beneficial for individuals with major depressive disorder (MDD). Healthy adults demonstrate significant cognitive gains after nature walks, but it was unclear whether those same benefits would be achieved in a depressed sample as walking alone in nature might induce rumination, thereby worsening memory and mood., Methods: Twenty individuals diagnosed with MDD participated in this study. At baseline, mood and short term memory span were assessed using the PANAS and the backwards digit span (BDS) task, respectively. Participants were then asked to think about an unresolved negative autobiographical event to prime rumination, prior to taking a 50-min walk in either a natural or urban setting. After the walk, mood and short-term memory span were reassessed. The following week, participants returned to the lab and repeated the entire procedure, but walked in the location not visited in the first session (i.e., a counterbalanced within-subjects design)., Results: Participants exhibited significant increases in memory span after the nature walk relative to the urban walk, p<.001, η(p)(2)=.53 (a large effect-size). Participants also showed increases in mood, but the mood effects did not correlate with the memory effects, suggesting separable mechanisms and replicating previous work., Limitations: Sample size and participants' motivation., Conclusions: These findings extend earlier work demonstrating the cognitive and affective benefits of interacting with nature to individuals with MDD. Therefore, interacting with nature may be useful clinically as a supplement to existing treatments for MDD., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Although analyzing negative experiences leads to physical and mental health benefits among healthy populations, when people with depression engage in this process on their own they often ruminate and feel worse. Here we examine whether it is possible for adults with depression to analyze their feelings adaptively if they adopt a self-distanced perspective. We examined this issue by randomly assigning depressed and nondepressed adults to analyze their feelings surrounding a depressing life experience from either a self-distanced or a self-immersed perspective and then examined the implications of these manipulations for depressotypic thought accessibility, negative affect, implicit and explicit avoidance, and thought content. Four key results emerged. First, all participants were capable of self-distancing while analyzing their feelings. Second, participants who analyzed their feelings from a self-distanced perspective showed lower levels of depressotypic thought accessibility and negative affect compared to their self-immersed counterparts. Third, analyzing negative feelings from a self-distanced perspective led to an adaptive shift in the way people construed their experience--they recounted the emotionally arousing details of their experience less and reconstrued them in ways that promoted insight and closure. It did not promote avoidance. Finally, self-distancing did not influence negative affect or depressotypic thought accessibility among nondepressed participants. These findings suggest that whether depressed adults' attempts to analyze negative feelings lead to adaptive or maladaptive consequences may depend critically on whether they do so from a self-immersed or a self-distanced perspective., (PsycINFO Database Record (c) 2012 APA, all rights reserved.)

Major depressive disorder (MDD) has been characterized by excessive default-network activation and connectivity with the subgenual cingulate. These hyper-connectivities are often interpreted as reflecting rumination, where MDDs perseverate on negative, self-referential thoughts. However, the relationship between connectivity and rumination has not been established. Furthermore, previous research has not examined how connectivity with the subgenual cingulate differs when individuals are engaged in a task or not. The purpose of the present study was to examine connectivity of the default network specifically in the subgenual cingulate both on- and off-task, and to examine the relationship between connectivity and rumination. Analyses using a seed-based connectivity approach revealed that MDDs show more neural functional connectivity between the posterior-cingulate cortex and the subgenual-cingulate cortex than healthy individuals during rest periods, but not during task engagement. Importantly, these rest-period connectivities correlated with behavioral measures of rumination and brooding, but not reflection.