The everyday dynamics of rumination and worry: precipitant events and affective consequences.

Rumination and worry are two perseverative, negatively valenced thought processes that characterise depressive and anxiety disorders. Despite significant research interest, little is known about the everyday precipitants and consequences of rumination and worry. Using an experience sampling methodology, we examined and compared rumination and worry with respect to their relations to daily events and affective experience. Participants diagnosed with Major Depressive Disorder (MDD), Generalized Anxiety Disorder (GAD), co-occurring MDD-GAD, or no diagnosis carried an electronic device for one week and reported on rumination, worry, significant events, positive affect (PA), and negative affect (NA). Across the clinical groups, occurrences of everyday events predicted subsequent increases in rumination, but not worry. Further, higher momentary levels of rumination, but not worry, predicted subsequent decreases in PA and increases in NA. Thus, in these clinical groups, rumination was more susceptible to daily events and produced stronger affective changes over time. We discuss implications for theory and clinical intervention.

Influence of menarche on the relation between diurnal cortisol production and ventral striatum activity during reward anticipation.

Adolescence is characterized by an increase in risk-taking and reward-seeking behaviors. In other populations, increased risk taking has been associated with tighter coupling between cortisol production and ventral striatum (VS) activation during reward anticipation; this relation has not yet been examined, however, as a function of adolescent development. This study examined the influence of pubertal development on the association between diurnal cortisol production and VS activity during reward anticipation. Pre- and post-menarcheal girls collected diurnal cortisol and completed an functional magnetic resonance imaging-based monetary incentive delay task, from which we extracted estimates of VS activity during the anticipation of reward, anticipation of loss and anticipation of non-incentive neutral trials. Post-menarcheal girls showed greater coupling between the cortisol awakening response and VS activation during anticipation of reward and loss than did their pre-menarcheal counterparts. Post-menarcheal girls did not differ from pre-menarcheal girls in their cortisol-VS coupling during anticipation of neutral trials, suggesting that puberty-related changes in cortisol-VS coupling are specific to affective stimuli. Interestingly, behavioral responses during the task indicate that post-menarcheal girls are faster to engage with affective stimuli than are pre-menarcheal girls. Thus, post-menarcheal girls exhibit neurobiological and behavioral patterns that have been associated with risk taking and that may underlie the dramatic increase in risk-taking behavior documented during adolescence.

Rumination and Worry in Daily Life: Examining the Naturalistic Validity of Theoretical Constructs.

Rumination and worry, two forms of perseverative thinking, hold promise as core processes that transect depressive and anxiety disorders. Whereas previous studies have been limited to the laboratory or to single diagnoses, we used experience sampling methods to assess and validate rumination and worry as transdiagnostic phenomena in the daily lives of individuals diagnosed with Major Depressive Disorder (MDD), Generalized Anxiety Disorder (GAD), and co-occurring MDD-GAD. Clinical and healthy control participants carried a hand-held electronic device for one week. Eight times per day they reported on their current levels of rumination and worry and their theoretically postulated features: thought unpleasantness, repetitiveness, abstractness, uncontrollability, temporal orientation, and content, and overall senses of certainty and control. Both rumination and worry emerged as transdiagnostic processes that cut across MDD, GAD, and MDD-GAD. Furthermore, most psychological theories concerning rumination and worry strongly mapped onto participants' reports, providing the first naturalistic validation of these constructs.

Activation of the medial prefrontal and posterior cingulate cortex during encoding of negative material predicts symptom worsening in major depression.

Considerable research indicates that depressed individuals have better memory for negative material than do nondepressed individuals, and that this bias is associated with differential patterns of neural activation. It is not known, however, whether these aberrant activation patterns predict illness course. Using functional neuroimaging, we examined whether change in depressive symptoms is predicted by baseline patterns of neural activation that underlie negative memory biases in major depressive disorder. Depressed participants viewed negative and neutral pictures during functional MRI at baseline and completed an incidental memory task for these pictures 1 week later. Depression severity was assessed by administering the Beck Depression Inventory both at baseline (Time 1) and at Time 2, an average of 18 months later. Contrast maps of activation for subsequently remembered negative versus subsequently remembered neutral pictures were regressed against change in Beck Depression Inventory scores between Time 1 and Time 2, controlling for initial symptom severity. Results from this analysis revealed no associations between memory sensitivity for negative stimuli and symptom change. In contrast, whole brain analyses revealed significant positive associations between within-subject changes in depressive symptoms and baseline neural activation to successfully recalled negative pictures in the posterior cingulate cortex and medial prefrontal cortex. These findings indicate that neural activation in cortical midline regions is a better predictor of long-term symptomatic outcome than is memory sensitivity for negative material.

Reward processing in adolescents with bipolar I disorder.

OBJECTIVE: Bipolar disorder (BD) is a debilitating psychiatric condition that commonly begins in adolescence, a developmental period that has been associated with increased reward seeking. Because youth with BD are especially vulnerable to negative risk-taking behaviors, understanding the neural mechanisms by which dysregulated affect interacts with the neurobehavioral processing of reward is clearly important. One way to clarify how manic symptoms evolve in BD is to "prime" the affect before presenting rewarding stimuli. The objective of this study was to investigate the neural effects of an affective priming task designed to positively induce mood before reward processing in adolescents with and without BD. METHOD: Neural activity and behaviors during the anticipation of and response to monetary reward and loss after an affective prime were compared using functional magnetic resonance imaging in 13- to 18-year-old adolescents with a recent onset of BD-I (n = 24) and demographically matched healthy comparison youth (n = 24). RESULTS: Compared with the healthy control youth, youth with BD had speeded reaction times and showed decreased activation in the thalamus and inferior temporal gyrus while anticipating gains after priming but increased activations in the middle frontal gyrus and parietal cortices while anticipating losses after priming. Youth with BD also showed less activation in the inferior parietal lobule, thalamus, and superior frontal gyrus while receiving losses after priming. CONCLUSIONS: Aberrant prefrontal and subcortical activations during reward processing suggest mechanisms that may underlie disordered self-awareness during goal pursuit and motivation in BD. Longitudinal studies are needed to examine whether this pattern of neural activation predicts a poorer long-term outcome.

Interacting with nature improves cognition and affect for individuals with depression.

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.

Anticipatory pleasure predicts motivation for reward in major depression.

Anhedonia, the lack of interest or pleasure in response to hedonic stimuli or experiences, is a cardinal symptom of depression. This deficit in hedonic processing has been posited to influence depressed individuals' motivation to engage in potentially rewarding experiences. Accumulating evidence indicates that hedonic processing is not a unitary construct but rather consists of an anticipatory and a consummatory phase. We examined how these components of hedonic processing influence motivation to obtain reward in participants diagnosed with major depression and in never-disordered controls. Thirty-eight currently depressed and 30 never-disordered control participants rated their liking of humorous and nonhumorous cartoons and then made a series of choices between viewing a cartoon from either group. Each choice was associated with a specified amount of effort participants would have to exert before viewing the chosen cartoon. Although depressed and control participants did not differ in their consummatory liking of the rewards, levels of reward liking predicted motivation to expend effort for the rewards only in the control participants; in the depressed participants, liking and motivation were dissociated. In the depressed group, levels of anticipatory anhedonia predicted motivation to exert effort for the rewards. These findings support the formulation that anhedonia is not a unitary construct and suggest that, for depressed individuals, deficits in motivation for reward are driven primarily by low anticipatory pleasure and not by decreased consummatory liking.

Identification of emotional facial expressions following recovery from depression.

This study investigated the identification of facial expressions of emotion in currently nondepressed participants who had a history of recurrent depressive episodes (recurrent major depression; RMD) and never-depressed control participants (CTL). Following a negative mood induction, participants were presented with faces whose expressions slowly changed from neutral to full intensity. Identification of facial expressions was measured by the intensity of the expression at which participants could accurately identify whether faces expressed happiness, sadness, or anger. There were no group differences in the identification of sad or angry expressions. Compared with CTL participants, however, RMD participants required significantly greater emotional intensity in the faces to correctly identify happy expressions. These results indicate that biases in the processing of emotional facial expressions are evident even after individuals have recovered from a depressive episode.