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Background: Motivational dysregulation represents a core vulnerability factor for bipolar disorder. Whether this also comprises aberrant learning of stimulus-reinforcer contingencies is less clear., Methods: To answer this question, we compared healthy first-degree relatives of individuals with bipolar disorder (n = 42) known to convey an increased risk of developing a bipolar spectrum disorder and healthy individuals (n = 97). Further, we investigated the effects of the behavioral activation system (BAS) on reinforcement learning across the entire sample. All participants were assessed with a probabilistic learning task that distinguishes learning from positive and negative feedback. Main outcome measures included choice frequencies and learning rate parameters generated by computational reinforcement learning algorithms., Results: First-degree relatives choose more rewarding stimuli more consistently and showed marginally reduced learning rates from unexpected negative feedback. Further, first-degree relatives had lower BAS scores than controls, which were negatively associated with learning rates from unexpected negative feedback., Limitations: However as probands also reported other mental disorders such as Attention-Deficit/Hyperactivity Disorder and substance abuse among their first-degree relatives, we cannot know, whether these findings are specific to the risk for bipolar disorder., Conclusion: The behavior of first-degree relatives of individuals with bipolar disorder, who also display increased BAS sensitivity, is less influenced by unexpected negative feedback. This reduced learning from unexpected negative feedback biases subsequent choices towards stimuli with higher probabilities for a reward. In sum, our results confirm the role of aberrant reinforcement learning in the pathophysiology of bipolar disorder., Competing Interests: Declaration of Competing Interest None of the authors has any conflict of interest., (Copyright © 2019. Published by Elsevier B.V.)

Background: Previous research suggests that bipolar disorder (BD) is characterized by deficits in cognitive control (CC). Impaired CC has been found in high-risk samples and is associated with the maintenance of BD symptoms. It remains unclear, however, whether BD is characterized by a general deficit in CC or by a deficit that is specifically related to the processing of emotional material., Methods: The sample consisted of 42 remitted bipolar patients and 39 healthy controls (HC). We examined whether BD individuals display impaired CC when confronted with negative as well as positive material using an arithmetic inhibition task that required inhibition of pictorial stimulus material., Results: Whereas both groups showed difficulties in exerting CC over negative material, only BD individuals exhibited deficient CC over positive material., Limitations: Even though we intended the negative and positive pictures in the arithmetic inhibition task to be similarly arousing, participants in the current study rated the negative compared to the positive pictures as more arousing., Conclusions: BD is associated with impaired CC when processing emotional - especially positive - stimuli even when patients are in remission. Possible implications of this deficit especially for emotion regulation are discussed., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Major depressive disorder (MDD) has been associated with empathy deficits. The exact nature of these deficits and their relation to concurrent alexithymia remain unknown. Here we tested under which conditions MDD patients with high and low alexithymia show deficient empathy, particularly investigating empathic abilities when inhibition of self-related emotional states is needed and when it is not., Methods: Healthy controls (low: n=28, high: n=14) and currently depressed MDD patients (low: n=11, high: n=18) with low or high alexithymia performed an emotional egocentricity paradigm based on tactile stimulation. This task measures empathic judgements, when emotional states of self and other differ and inhibition of self-related emotional states is needed, and when they do not and thus empathic judgments can be based on simple projection mechanisms., Results: Only alexithymia but not depression decreased empathy, in situations when simple projection sufficed. However, when inhibition of self-related emotional states was needed, MDD patients showed an egocentric bias during empathic judgments and an altercentric bias during self emotion judgments, the latter suggesting heightened emotional contagion, both independent of alexithymia. Across the entire sample, alexithymia decreased the size of the egocentric bias., Limitations: This study was based on a relatively sample size., Conclusions: These results suggest that MDD patients show intact empathic judgments, when simple projection is required and no concurrent alexithymia is present. In situations when incongruent emotional states of self and other have to be resolved, MDD patients are prone to egocentric and altercentric biases., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Self-generated thoughts (SGTs), such as during mind wandering, occupy much of our waking life. Individuals with Major Depressive Disorder (MDD) are less in the "here and now" and prone to rumination. Few studies have looked at SGTs in depression using experience sampling methods and no study has so far investigated the specific contents of depressive SGTs and how they vary from one time point to another., Methods: MDD patients (n=25) and matched healthy controls (n=26) performed an established mind wandering task, involving non-demanding number discriminations. Intermittent probe questions ask for participants' current SGTs, that is, how off-task the thoughts are, how positive or negative, self- or other-related, and past- or future-oriented., Results: Multi-level modelling revealed that MDD patients engaged in more mind wandering than healthy controls. Their SGTs were predominantly negative and less positive, more self-related and past-oriented. Strongest predictor of depressive SGT was the decreased positive valence of thoughts. MDD patients' future and past-oriented thoughts were particularly more negative compared to healthy controls. Within MDD patients, the less positively valenced thoughts they had and the less variable these thoughts were, the more depressive symptoms they showed., Limitation: No other measures of rumination and worry were used., Conclusion: MDD patients show a very specific SGT pattern, possibly reflecting ruminative and anxious thoughts. This SGT pattern in depression might represent a useful state marker and even constitute an etiological factor of this debilitating disease, considering the importance of current SGT on and individual's cognitive processes and affective states., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Heightened impulsivity has been suggested as a possible risk factor for bipolar disorder (BD). However, studies on high-risk populations are scarce and have mainly focused on individuals with a genetic risk. The present study investigated two high-risk samples for BD with regard to several aspects of the impulsivity construct., Methods: Unaffected relatives of BD patients (genetically defined high-risk group, N=29) and participants scoring high on the Hypomanic Personality Scale (psychometrically defined high-risk sample, N=25) were being compared to respective control groups (N=27 and N=25) using a multi-method approach. Participants were accessed on the Barratt Impulsiveness Scale-11 (BIS-11, trait impulsivity), the Stop Signal Task (response inhibition), and the Cambridge Gambling Task (impulsive behavior in decision-making processes)., Results: Both high-risk groups reported heightened impulsivity on the BIS-11, as well as impulsive decision-making, whereas no significant group differences in response inhibition were observed., Limitations: Limitations were the lack in specificity of the results for BD and the cross-sectional study design, which does not allow conclusions about the influence of impulsivity on the development of or resilience for BD in risk groups., Conclusions: Our findings support the assumption that increased trait impulsivity and impulsive decision-making are a vulnerability marker for and an endophenotype of BD., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Objective: Emotion regulation deficits are a key characteristic of bipolar disorder (BD). In the present study, we asked if deficits in emotion regulation are also a vulnerability marker for BD. To this end, we investigated a healthy group of participants at high-risk for developing BD, defined on the basis of a hypomanic personality trait. We examined the neural correlates of two emotion regulation strategies, reappraisal and distraction., Method: Twenty-two individuals with higher risk for BD and twenty-four controls were investigated in a functional magnetic resonance imaging paradigm. Participants were presented with negative, positive and neutral pictures and were either required to passively view the images, to down-regulate the emotional response by reappraising the pictures' content, or to perform a distracting arithmetic task., Results: High-risk individuals showed increased emotional reactivity to negative stimuli, indicated by heightened amygdala activation during passive viewing. High-risk participants were also less successful in down-regulating amygdala activity using reappraisal of negative stimuli. During distraction from positive stimuli, high-risk individuals showed heightened task-related activity in the inferior parietal cortex, suggesting increased distractibility by task-irrelevant positive background stimuli. There were no differences in habitual emotion regulation as assessed by a self-report questionnaire., Limitations: Generalizability of the present results is limited by the age- and education-homogenous sample and the small sample size., Conclusions: This is the first study to report neural correlates of increased emotional reactivity and deficient emotion regulation in healthy individuals at risk for BD. These findings suggest inefficient emotion regulation through reappraisal and distraction in individuals with high hypomanic personality who are supposed to be at higher risk to develop bipolar disorder., (Copyright © 2013 Elsevier B.V. All rights reserved.)