Biology subjects

Krach, S.

Publications and source records attributed to Krach, S..

16 recordsLinked to original sources

bioRxiv2026

Self-enhancement and devaluation of others during belief formation are linked to narcissistic traits

Background: Narcissistic personality traits are associated with the tendency to maintain a grandiose self-image through self-enhancement and devaluation of others. Using computational modeling, we investigated how narcissistic traits and the experience of pride are linked to how individuals form beliefs about themselves and others. Methods: Healthy individuals and individuals with psychiatric diagnoses varying in narcissistic traits (N = 97) completed a learning task in which self-serving biases emerged implicitly through trial-by-trial belief updating in response to manipulated feedback. Computational modeling quantified how participants updated beliefs about their own and another person's abilities in response to better- and worse-than-expected performance feedback. Results: Higher narcissistic traits were associated with reduced learning from worse-than-expected self-related feedback, consistent with self-enhancement as a mechanism for maintaining a grandiose self-image. Individuals with higher narcissistic traits also reported greater pride following better-than-expected self-related feedback, which mediated the association between narcissistic traits and positive self-related learning. Furthermore, higher narcissistic traits were, mediated via pride, linked to increased learning from worse-than-expected feedback about the other person, suggesting that devaluing others relative to oneself may serve as a secondary pathway for maintaining a grandiose self-image. Discussion: These findings identify computational and affective mechanisms through which narcissistic traits are linked to self- and other-related belief formation. Reduced integration of negative self-related feedback together with enhanced pride following positive feedback may support grandiose self-beliefs, while enhanced learning from negative information about others suggests that individuals with higher narcissistic traits implicitly construct themselves as superior through both self-enhancement and devaluation of others during interpersonal belief formation.

neuroscience↗

bioRxiv2026

The role of sleep in the retention and long-term maintenance of newly formed ability self-beliefs

Sleep supports the consolidation of newly acquired information, however its role in the formation of self-beliefs has not yet been examined. Here, we investigated whether sleep facilitates the retention, stabilization, revision and long-term maintenance of newly formed ability beliefs. Using a Sleep vs. Wake between-subjects design (N=54), participants completed the Learning Of Own Performance (LOOP) task, which allowed them to form new positive and negative ability self-beliefs based on mocked feedback at a first session, and to revise them when encountering contradictory feedback at a second session. Belief formation was followed by either a sleep or wake retention interval. Belief states were tested at four time points: immediately after belief formation, after the 12-h retention interval, following the revision phase and after three weeks. Participants successfully formed and revised self-beliefs using the LOOP task. Compared with wakefulness, sleep following belief formation did not affect belief retention across the 12-h interval, nor did it stabilize beliefs against their revision. However, after three weeks, participants who slept after belief formation showed a shift towards more positivity for the initially formed low ability self-beliefs. Contrary to our hypotheses, sleep did not enhance short-term retention or stabilization of newly formed self-beliefs. However, the more positively recalled ability self-belief associated with the initially low-performance condition suggest that sleep may facilitate a positive long-term shift.

neuroscience↗

bioRxiv2026

Interleukin-6 responses to acute stress are not altered in alcohol use disorder despite elevated baseline inflammation

Acute stress activates the immune system, leading to the release of pro-inflammatory cytokines, such as interleukin-6 (IL-6). Chronic alcohol consumption alters the physiological stress systems and is associated with increased chronic inflammation. However, it remains unclear how IL-6 responds to acute stress in individuals with alcohol use disorder (AUD). Forty patients with AUD during early abstinence and 37 healthy controls (HC) completed two study visits. On one day, an acute stress induction task was performed, and on the other, a non-stressful control task, with the order of tasks being balanced. Plasma IL-6 and C-reactive protein (CRP) were measured as inflammatory markers at baseline and changes in IL-6 were assessed 90 minutes after the experimental manipulation. Patients with AUD showed significantly elevated baseline IL-6 and CRP compared to HC and the levels correlated positively with the amount of consumed alcohol in patients. IL-6 responses to the stress intervention did not differ between groups. Increases in IL-6 were observed on stress and control days and were larger when samples were collected via an indwelling catheter than with a butterfly needle. These findings suggest that IL-6 responses to acute stress do not differ between AUD and HC, despite increased baseline inflammation. Furthermore, the results indicate that blood collection methods can influence IL-6 measurements and highlight the importance of methodological considerations.

immunology↗

bioRxiv2025

Self-compassion is linked to positive affect and buffers declines in self-esteem in low performers

Successes and failures shape affective experience and self-esteem. Self-compassion has been proposed as a protective factor, allowing individuals to acknowledge both strengths and shortcomings without excessive self-criticism. However, the mechanisms through which self-compassion influences changes in affect and self-esteem remain poorly understood. Here, we experimentally tested whether self-compassion modulates the links between performance feedback, affective experience, and self-esteem. Participants completed an effortful performance task and received trial-by-trial feedback while repeatedly rating their positive affect. Results show that self-compassion buffered against declines in self-esteem among poorly performing individuals, predicted higher overall positive affect throughout the task, and was associated with increased post-task self-esteem. Moreover, performance feedback predicted positive affect, which in turn predicted post-task self-esteem, although these pathways were not moderated by self-compassion. Together, these findings add to the growing evidence for how self-compassion impacts positive affect and self-esteem and may inform treatment strategies for clinical populations characterized by low self-esteem or heightened self-criticism.

neuroscience↗

bioRxiv2025

Self-esteem modulates beneficial causal attributions in the formation of novel self-beliefs

Healthy individuals typically attribute successes to internal causes, such as their abilities, and failures to external factors, like bad luck. In contrast, individuals with depression and low self-esteem are more likely to attribute failures to internal causes and successes to external causes. At the same time, depression and low self-esteem are associated with negatively biased self-related learning and self-beliefs. Although causal attributions have been shown to influence belief formation and updating, the dynamic interaction between real-time attributions and self-related learning remains poorly understood. In this study, we used a validated self-related learning task to investigate how internal versus external attributions of performance feedback affect the formation of self-beliefs and how these processes relate to depressive symptoms and self-esteem. Drawing on a computational model that incorporates prediction error valence and causal attributions, we found that participants updated their self-beliefs less when feedback was attributed to external causes. Furthermore, individuals with higher levels of depression and lower self-esteem showed a stronger negativity bias in learning. Lower self-esteem was also linked to a reduced self-serving bias in attributions. These findings provide insight into the cognitive mechanisms that may contribute to the development and maintenance of negative self-beliefs commonly observed in depression.

neuroscience↗

bioRxiv2025

No neurobehavioral evidence for reduced motivational potential of social rewards in alcohol use disorder

BackgroundThe mesolimbic dopamine system plays a central role in motivating behavior. In alcohol use disorder (AUD), this system is thought to be dysfunctional, leading to hyperreactivity to alcohol-related cues. In contrast, evidence on how individuals with AUD respond to alcohol-unrelated reward cues is inconclusive, and the motivation for social rewards has not yet been investigated. MethodsTo address this gap, 36 individuals with AUD and 34 healthy controls performed an incentive delay task to assess social reward anticipation with a monetary and a non-reward control condition while undergoing functional magnetic resonance imaging. The ventral striatum was defined as region of interest because of its central role in neuronal circuits for motivation. ResultsNeither behavioral nor neuroimaging data provided any evidence of reduced motivation for social or monetary rewards in AUD. Exploratory whole-brain analyses only revealed stronger activation in the occipital/cuneal cortex in individuals with AUD than in healthy controls across all trials. ConclusionTogether, these results suggest that sensitivity to social reward cues is not fundamentally impaired in AUD. Furthermore, they imply that motivational changes related to the substance do not generally alter the reward potential of alcohol-unrelated domains in AUD, opening perspectives for social-behavioral treatments for this disorder.

neuroscience↗

bioRxiv2024

Time-of-day related fluctuations of self-belief formation

Time of day influences a variety of human cognitive processes, including attention, executive functions and memory formation, as well as affective experiences and mood. However, circadian modulations of self-related learning and belief formation, which are highly affected by emotional states, remain poorly understood. Here, we present results from exploratory post-hoc analyses on data aggregated from five studies assessing the formation of self-related ability beliefs. A total of N=242 healthy participants completed a validated learning task at different times of the day, during which they continuously received feedback on their performance. Computational modeling was applied to quantify participants learning behavior during the task. Results suggest an association between time-of-day and self-belief formation, showing that participants who were tested in the evening (7:00-9:59 p.m.) updated their self-beliefs more strongly in response to the received feedback compared to those tested in the afternoon (1:00-3:59 p.m.). Evidence from additional models indicated that these differences were driven by non-linear, rhythmic changes in self-belief formation across different times of the day. Future studies should systematically examine within-subject fluctuations in self-belief formation across the day and address the influence of individual factors such as chronotype, age, mood and sleep quality. Understanding circadian modulations of self-related belief formation could contribute to optimized interventions for conditions characterized by maladaptive self-beliefs, such as depression, as well as in academic contexts.

neuroscience↗

bioRxiv2024

Computational Modeling shows Confirmation Bias during Formation and Revision of Self-Beliefs

Self-beliefs hinge on social feedback, but their formation and revision are not solely based on new information. Biases, such as confirming initial expectations, can lead to inaccurate self-beliefs. This study uses computational modeling to explore how initial expectations and confidence affect self-belief formation and revision in novel behavioral domains. In the first session, participants developed performance self-beliefs through trial-by-trial feedback. In the second session, feedback contingencies were reversed, requiring belief revision for accurate self-beliefs. Results showed a confirmation bias in belief updating, with initial expectations being linked to biased learning during both formation and revision. Higher confidence was associated with reduced belief revision and on average, self-beliefs persisted despite the conflicting evidence. This study extends the literature on confirmation bias to learning in uncharged, novel behavioral domains. Further, it demonstrates the importance of initial expectations and associated confidence for biased self-belief formation and subsequent learning.

neuroscience↗

bioRxiv2024

Neurocomputational Mechanisms Underlying Maladaptive Self-Belief Formation in Depression

Maladaptive self-beliefs are a core symptom of major depressive disorder. These beliefs are perpetuated by a negatively biased integration of self-related feedback. Understanding the neurocomputational mechanisms of biased belief updating may help to counteract maladaptive beliefs and the maintenance of depression. The present study uses a belief-updating task and functional neuroimaging to examine the neurocomputational mechanisms associated with self-related feedback processing in individuals with major depression and matched healthy controls. We hypothesized that increased symptom burden in depression is associated with negatively biased self-belief updating and altered neural tracking of social feedback. Our findings show that depression is related to reduced incorporation of unexpected positive feedback, with higher symptom burden alongside heightened insula reactivity to unexpected negative feedback. The interplay of increased neural responsiveness to negative feedback and the reduced learning from positive feedback provide new insights into cognitive distortions in depression and may explain the persistence of maladaptive self-beliefs and, thus, the maintenance of depression.

neuroscience↗

bioRxiv2024

Altered physiological, affective, and functional connectivity responses to acute stress in patients with alcohol use disorder

BackgroundThere is evidence that the processing of acute stress is altered in alcohol use disorder (AUD), but little is known about how this is manifested simultaneously across different stress parameters and which neural processes are involved. The present study examined physiological and affective responses to stress and functional connectivity in AUD. MethodsSalivary cortisol samples, pulse rate, and affect ratings were collected on two days from 34 individuals with moderate or severe AUD and 34 controls. On one day, stress was induced, and on the other day, a non-stressful control task was performed. Following the intervention, participants underwent fMRI to assess functional connectivity, focusing on cortical and subcortical seed regions previously reported to be involved in AUD and/or stress. ResultsFor pulse rate and cortisol, stress responses were blunted in AUD, whereas negative affect was increased. Furthermore, stress-related changes in pulse rate, cortisol, and affect were only correlated in healthy controls. Neuroimaging analyses revealed stress-related group differences in functional connectivity, involving the connectivity of striatal seeds with the posterior DMN, cerebellum and midcingulate cortex, and of the posterior DMN seed with the striatum and thalamus. ConclusionsThe results suggest a dissociation between subjective experienced distress and the physiological stress response in AUD as well as stress-related alterations in functional connectivity. These findings highlight the complex interplay between chronic alcohol use and acute stress regulation, offering valuable considerations for the development of therapeutic strategies.

neuroscience↗

bioRxiv2021

Computational and neural mechanisms of affected beliefs

The feedback people receive on their behavior shapes the process of belief formation and self-efficacy in mastering a given task. However, the neural and computational mechanisms of how the subjective value of these beliefs, and the corresponding affect, bias the learning process remain unclear. We investigated these mechanisms during the learning of self-efficacy beliefs using fMRI, pupillometry, and computational modeling, and by analyzing individual differences in affective experience. Biases in the formation of self-efficacy beliefs were associated with affect, pupil dilation, and neural activity within the anterior insula, amygdala, ventral tegmental area/ substantia nigra, and mPFC. Specifically, neural and pupil responses map the valence of the prediction errors in correspondence with individuals experienced affect and learning bias during belief formation. Together with the functional connectivity dynamics of the anterior insula within this network, our results hint at neural and computational mechanisms that integrate affect into the process of belief formation.

neuroscience↗

bioRxiv2021

Association of stress-related limbic activity and baseline interleukin-6 plasma levels in healthy adults

Several studies suggest a link between acute changes in inflammatory parameters due to an endotoxin or (psychological) stressor and the brains stress response. The extent to which basal circulating levels of inflammatory markers are associated with the brains stress response has been hardly investigated so far. In the present study, baseline plasma levels of the cytokine interleukin (IL)-6 were obtained and linked to neural markers of psychosocial stress using a modified version of the Montreal Imaging Stress Task in a sample of N=65 healthy subjects (N=39 female). Of three a-priori defined regions of interest - the amygdala, anterior insula, and anterior cingulate cortex - baseline IL-6 was significantly and negatively associated with stress-related neural activation in the right amygdala and left anterior insula. Our results suggest that baseline cytokines might be related to differences in the neural stress response and that this relationship could be inverse to that previously reported for induced acute changes in inflammation markers.

neuroscience↗

bioRxiv2020

Self-beneficial belief updating as a coping mechanism for stress-induced negative affect

Being confronted with social-evaluative stress elicits a physiological and a psychological stress response. This calls for regulatory processes to manage negative affect and maintain self-related optimistic beliefs. The aim of the current study was to investigate the affect-regulating potential of self-related belief updating after exposure to social-evaluative stress, in comparison to non-social physical stress or no stress. We assessed self-related belief updating using trial-by-trial performance feedback and described the updating behavior in a mechanistic way using computational modeling. We found that social-evaluative stress was accompanied by an increase in cortisol and negative affect which was related to a shift in self-related belief updating towards the positive direction. This self-beneficial belief updating, which was absent after physical stress or control, was associated with a better recovery from stress-induced negative affect. This indicates that enhanced integration of positive self-related feedback can act as a coping strategy to deal with social-evaluative stress.

neuroscience↗

bioRxiv2020

Selective REM-Sleep Suppression Increases Next-Day Negative Affect and Amygdala Responses to Social Exclusion

Healthy sleep, positive general affect, and the ability to regulate emotional experiences are fundamental for well-being. In contrast, various mental disorders are associated with altered rapid eye movement (REM) sleep, negative affect, and diminished emotion regulation abilities. However, the neural processes mediating the relationship between these different phenomena are still not fully understood. In the present study of 42 healthy volunteers, we investigated the effects of selective REM sleep suppression (REMS) on general affect, as well as on feelings of social exclusion, emotion regulation, and their neural underpinnings. Using functional magnetic resonance imaging we show that REMS increases amygdala responses to experimental social exclusion, as well as negative affect on the morning following sleep deprivation. There was no evidence that emotional responses to experimentally induced social exclusion or their regulation using cognitive reappraisal were impacted by diminished REM sleep. Our findings indicate that general affect and amygdala activity depend on REM sleep, while specific emotional experiences possibly rely on additional psychological processes and neural systems that are less readily influenced by REMS.

neuroscience↗

bioRxiv2019

Subjectively perceived control drives affective, neural, and motivational markers of self-related outcome valuation

Experiencing events as controllable and attributing positive outcomes to own contributions is essential for human well-being. Based on classic psychological theory we test how internal control beliefs impact the affective valuation of task outcomes, neural dynamics and ensuing behavioral preferences. In three consecutive studies with independent samples we show that dynamics in self-evaluative affect specifically increase when agents believe they caused a given task outcome. We demonstrate that these outcomes engage brain networks processing self-referential information in the cortical midline. Here, activity in the ventromedial prefrontal cortex tracks outcome valence regarding both success as well as internal control, and covaries with self-evaluative affect. These affective dynamics also relate to increased functional coupling between the ventral striatum and cortical midline structures. Finally, we show that self-evaluative affect promotes preferences for control, even at a monetary cost. Our investigations extend recent models of positive affect and well-being, and emphasize that control beliefs drive intrinsic motivation.

neuroscience↗

bioRxiv2017

The impact factor fallacy

The use of the journal impact factor (JIF) as a measure for the quality of individual manuscripts and the merits of scientists has faced significant criticism in recent years. We add to the current criticism in arguing that such an application of the JIF in policy and decision making in academia is based on false beliefs and unwarranted inferences. To approach the problem, we use principles of deductive and inductive reasoning to illustrate the fallacies that are inherent to using journal based metrics for evaluating the work of scientists. In doing so, we elaborate that if we judge scientific quality based on the JIF or other journal based metrics we are either guided by invalid or weak arguments or in fact consider our uncertainty about the quality of the work and not the quality itself.

scientific communication and education↗