Biology subjects

Schröder, A.

Publications and source records attributed to Schröder, A..

7 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

A tunable receptor separates root barrier formation from nutrient signaling through ligand-perception states

In roots, the endodermis controls nutrient entry by forming a barrier known as the Casparian strip1-3. Yet how barrier-associated processes interface with systemic signaling remains unclear. Here, we show that the receptor kinase SCHENGEN3 links local barrier surveillance to systemic nutrient signaling, with outputs that depend on the effective state of ligand perception. Unlike in Arabidopsis thaliana, SCHENGEN3 activation in Lotus japonicus requires a distinct cellular competence state and cannot be triggered by exogenous ligands alone, revealing evolutionary divergence in pathway deployment. Cross-species complementation uncouples systemic nitrogen signaling from Casparian strip formation, while transcriptomic and phosphoproteomic analyses reveal largely non-overlapping signaling- and barrier-associated programs that differ between agar and agricultural soil conditions. Mechanistically, receptor-ligand comparisons, engineered receptor variants, and co-receptor mutant analyses show that systemic nitrogen signaling is retained in receptor-perception states that are insufficient to support full Casparian strip establishment. Together, these findings reveal how a shared receptor module can separate developmental and physiological outputs by linking receptor perception state to output specificity.

plant biology↗

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

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↗

bioRxiv2017

Spatial modeling of the membrane-cytosolic interface in protein kinase signal transduction

The spatial architecture of signaling pathways and the inter-action with cell size and morphology are complex but little understood. With the advances of single cell imaging and single cell biology it becomes crucial to understand intracel-lular processes in time and space. Activation of cell surface receptors often triggers a signaling cascade including the activation of membrane-attached and cytosolic signaling components, which eventually transmit the signal to the cell nucleus. Signaling proteins can form steep gradients in the cytosol, which cause strong cell size dependence. We show that the kinetics at the membrane-cytosolic interface and the ratio of cell membrane area to the enclosed cytosolic volume change the behavior of signaling cascades significantly. We present a mathematical analysis of signal transduction in time and space by providing analytical solutions for different spatial arrangements of linear signaling cascades. These investigations are complemented by numerical simulations of non-linear cascades and asymmetric cell shapes.

systems biology↗