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Research has focused on identifying neurobiological risk factors associated with aggressive behavior in order to improve prevention and treatment efforts. This study aimed to characterize microstructural differences in white matter (WM) integrity in individuals prone to aggression. We hypothesized that altered cerebral WM microstructure may underlie normal individual variability in aggression and tested this using a case-control design in healthy individuals. Diffusion tensor imaging (DTI) was used to examine WM changes in martial artists (n = 29) and age-matched controls (n = 31). We performed tract-based spatial statistics (TBSS) to identify differences in axial diffusivity (AD), fractional anisotropy (FA) and mean diffusivity (MD) between the two groups at the whole-brain level. Martial artists were significantly more aggressive than controls, with increased MD in parietal and occipital areas and increased AD in widespread fiber tracts in the frontal, parietal and temporal areas. Positive associations between AD/MD and (physical) appetitive aggression were identified in several clusters, including the corpus callosum, the superior longitudinal fasciculus and the corona radiata. Our study found evidence for WM microstructural changes associated with aggressiveness in a community case-control sample. Longitudinal studies with larger cohorts, taking into account the dimensional nature of aggressiveness, are needed to better understand the underlying neurobiology., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

The brain's default mode network (DMN) and the executive control network (ECN) switch engagement are influenced by the ventral attention network (VAN). Alterations in resting-state functional connectivity (RSFC) within this so-called triple network have been demonstrated in patients with major depressive disorder (MDD) or anxiety disorders (ADs). This study investigated alterations in the RSFC in patients with comorbid MDD and ADs to better understand the pathophysiology of this prevalent group of patients. Sixty-eight participants (52.9% male, mean age 35.3 years), consisting of 25 patients with comorbid MDD and ADs (MDD + AD), 20 patients with MDD only (MDD) and 23 healthy controls (HCs) were investigated clinically and with 3T resting-state fMRI. RSFC utilizing a seed-based approach within the three networks belonging to the triple network was compared between the groups. Compared with HC, MDD + AD showed significantly reduced RSFC between the ECN and the VAN, the DMN and the VAN and within the ECN. No differences could be found for the MDD group compared with both other groups. Furthermore, symptom severity and medication status did not affect RSFC values. The results of this study show a distinct set of alterations of RSFC for patients with comorbid MDD and AD compared with HCs. This set of dysfunctions might be related to less adequate switching between the DMN and the ECN as well as poorer functioning of the ECN. This might contribute to additional difficulties in engaging and utilizing consciously controlled emotional regulation strategies., (© 2024 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Deficits in reward learning are core symptoms across many mental disorders. Recent work suggests that such learning impairments arise by a diminished ability to use reward history to guide behaviour, but the neuro-computational mechanisms through which these impairments emerge remain unclear. Moreover, limited work has taken a transdiagnostic approach to investigate whether the psychological and neural mechanisms that give rise to learning deficits are shared across forms of psychopathology. To provide insight into this issue, we explored probabilistic reward learning in patients diagnosed with major depressive disorder (n = 33) or schizophrenia (n = 24) and 33 matched healthy controls by combining computational modelling and single-trial EEG regression. In our task, participants had to integrate the reward history of a stimulus to decide whether it is worthwhile to gamble on it. Adaptive learning in this task is achieved through dynamic learning rates that are maximal on the first encounters with a given stimulus and decay with increasing stimulus repetitions. Hence, over the course of learning, choice preferences would ideally stabilize and be less susceptible to misleading information. We show evidence of reduced learning dynamics, whereby both patient groups demonstrated hypersensitive learning (i.e. less decaying learning rates), rendering their choices more susceptible to misleading feedback. Moreover, there was a schizophrenia-specific approach bias and a depression-specific heightened sensitivity to disconfirmational feedback (factual losses and counterfactual wins). The inflexible learning in both patient groups was accompanied by altered neural processing, including no tracking of expected values in either patient group. Taken together, our results thus provide evidence that reduced trial-by-trial learning dynamics reflect a convergent deficit across depression and schizophrenia. Moreover, we identified disorder distinct learning deficits., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Guarantors of Brain.)

Aggression occurs across the population ranging on a symptom continuum. Most previous studies have used magnetic resonance imaging in clinical/forensic samples, which is associated with several confounding factors. The present study examined structural brain characteristics in two healthy samples differing only in their propensity for aggressive behavior. Voxel- and surface-based morphometry (SBM) analyses were performed on 29 male martial artists and 32 age-matched male controls. Martial artists had significantly increased mean gray matter volume in two frontal (left superior frontal gyrus and bilateral anterior cingulate cortex) and one parietal (bilateral posterior cingulate gyrus and precuneus) brain clusters compared to controls (whole brain: p < 0.001, cluster level: family-wise error (FWE)-corrected). SBM analyses revealed a trend for greater gyrification indices in martial artists compared to controls in the left lateral orbital frontal cortex and the left pars orbitalis (whole brain: p < 0.001, cluster level: FWE-corrected). The results indicate brain structural differences between martial artists and controls in frontal and parietal brain areas critical for emotion processing/inhibition of emotions as well as empathic processes. The present study highlights the importance of studying healthy subjects with a propensity for aggressive behavior in future structural MRI research on aggression., (© 2023. The Author(s).)

Background: Childhood trauma (CT) increases vulnerability for the development of major depressive disorder (MDD). Alterations in resting-state functional connectivity (RSFC) have frequently been reported for MDD. These alterations may be much more prominent in depressive patients with a history of CT. The present study aims to compare RSFC in different brain networks of patients with MDD and CT (MDD+CT) vs. MDD and no CT compared to healthy controls., Methods: 45 patients (22 with CT) were compared to 23 age-and-gender-matched healthy control subjects. Demographic parameters, severity of MDD, severity of CT and comorbid anxiety disorders were assessed. For assessment of RSFC alterations, a seed-based approach within five well-established RSFC networks was used., Results: CT in MDD patients predicts severity of comorbid anxiety. A significant decrease in in-between network RSFC-values of MDD patients compared to controls was found in the network pairs of default mode network (DMN) - dorsal attention network (DAN), ventral attention network (VAN) - DMN and DAN - affective network (AN). MDD+CT patients presented more aberrant RSFC than MDD-CT patients. MDD scores predicted the decrease in RSFC for MDD patients. Higher Childhood Trauma Questionnaire (CTQ) scores are linked to reduced functional connectivity (FC) between DMN - DAN., Conclusions: Our study shows reduced RSFC in MDD patients for DMN - DAN, VAN - DMN, DAN - AN and MDD+CT patients presented more aberrant RSFC so that we suspect CT to be a considerable factor in the etiology of MDD. Through dysregulated neural circuits, CT is likely to contribute to a distinct MDD pathophysiology., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background: The global pandemic of the coronavirus disease 2019 (COVID-19) has presented many unique challenges to health systems. The hidden impact of COVID-19 and its associated lockdown have been an increased prevalence of domestic violence., Objective: To increase our understanding of the connection between COVID-19 containment measures, domestic violence, and mental health in Germany, we conducted an online self-assessment survey of 98 domestic violence victims and 276 controls. All participants answered questions concerning domestic violence, emotional regulation skills, limitations due to and acceptance of containment measures, and quality of their contact experiences., Results: There was no significant effect of "gender" x "domestic violence." Among victims of domestic violence, the number of women was considerably higher than the number of men. In addition, the factors "negative contact quality," "emotional regulation," and "resilience" differed significantly between the victims of domestic violence and the control group., Conclusions: The COVID-19 outbreak and associated containment and quarantine measures resulted in a "hidden pandemic" of domestic violence for which prevention programs and early victim assistance through the expansion of digital technologies are urgently needed. Prospective studies should expand empirical data to focus on the long-term psychological effects of domestic violence and biomarkers that can serve as warning signs of stress-related disorders., (© 2023. The Author(s), under exclusive license to Springer Nature Switzerland AG.)

Objectives: Major Depression (MDD) and anxiety disorders are stress-related disorders that share pathophysiological mechanisms. There is evidence for alterations of glutamate-glutamine, N-acetylaspartate (NAA) and GABA in the anterior cingulate cortex (ACC), a stress-sensitive region affected by hypothalamic-pituitary-adrenal axis (HPA). The aim was to investigate metabolic alterations in the ACC and whether hair cortisol, current stress or early life adversity predict them., Methods: We investigated 22 patients with MDD and comorbid anxiety disorder and 23 healthy controls. Proton magnetic resonance spectroscopy was performed with voxels placed in pregenual (pg) and dorsal (d) ACC in 3 T. Analysis of hair cortisol was performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS)., Results: The N-acetylaspartate/Creatin ratio (NAA/Cr) was reduced in patients in both pgACC ( p  = .040) and dACC ( p  = .016). A significant interactive effect of diagnosis and cortisol on both pg-NAA/Cr (F = 5.00, p  = .033) and d-NAA/Cr (F = 7.86, p  = .009) was detected, whereby in controls cortisol was positively correlated with d-NAA/Cr (r = 0.61, p  = .004)., Conclusions: Our results suggest a relationship between NAA metabolism in ACC and HPA axis activity as represented by long-term cortisol output.

Background: Several studies in major depressive disorder (MDD) have found inflammation, especially C-reactive protein (CRP), to be consistently associated with MDD and network dysfunction. The aim was to investigate whether CRP is linked to a distinct set of resting-state functional connectivity (RSFC) alterations., Methods: For this reason, we investigated the effects of diagnosis and elevated blood plasma CRP levels on the RSFC in 63 participants (40 females, mean age 31.4 years) of which were 27 patients with a primary diagnosis of MDD and 36 healthy control-subjects (HC), utilizing a seed-based approach within five well-established RSFC networks obtained using fMRI., Results: Of the ten network pairs examined, five showed increased between-network RSFC-values unambiguously connected either to a diagnosis of MDD or elevated CRP levels. For elevated CRP levels, increased RSFC between DMN and AN was found. Patients showed increased RSFC within DMN areas and between the DMN and ECN and VAN, ECN and AN and AN and DAN., Conclusions: The results of this study show dysregulated neural circuits specifically connected to elevated plasma CRP levels and independent of other alterations of RSFC in MDD. This dysfunction in neural circuits might in turn result in a certain immune-inflammatory subtype of MDD., (Copyright © 2022. Published by Elsevier B.V.)

Aggression can have a hedonistic aspect in predisposed individuals labeled as appetitive aggression. The present study investigates the neurobiological correlates of this appetitive type of aggression in non-clinical samples from community. Applying functional magnet resonance imaging (fMRI), we tested whether 20 martial artists compared to 26 controls had a higher activation in the nucleus accumbens (NAcc), a central part of the dopaminergic, mesolimbic reward system. Subjects had to watch violent vs. neutral pictures representing appetitive aggression. The affinity towards hedonistic violence was assessed by the Appetitive and Facilitative Aggression Scale (AFAS). Furthermore, the subjects rated all the pictures with regard to how pleasant and violent they were. The martial artists reported a higher AFAS-score and a more positive perception of violent pictures. On the neural level, across all subjects, there was a significant positive correlation between the AFAS-score and the activation in the left NAcc and an inverse association with the activation of the right NAcc when watching violent compared to neutral pictures. This lateralization effect indicates a different processing of hedonistic aspects of aggression in the two hemispheres., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Objectives: The direct exertion as well as the visual perception of violence can have a hedonistic effect and elicit positive arousal in predisposed individuals. This appetitive aspect of aggression in healthy subjects has been neglected in psychiatric research so far., Methods: Using functional magnetic resonance imaging, we tested whether subjects trained in sports with a violent component (martial arts) show altered brain responses in reward-associated brain areas when compared to controls. Sixteen martial artists (e.g., boxing, mixed martial arts) and 24 controls watched violent versus neutral pictures while performing a cognitive cover task. Subjects' aggressiveness was assessed by the aggressiveness factors questionnaire (FAF)., Results: While watching violent pictures, martial artists had a stronger activation in the left amygdala than controls. Within the martial artist group however, there was an inverse correlation between activation in the left amygdala and degree of aggressiveness., Conclusions: Higher amygdala activation while watching violent pictures might reflect that perception of violence conveys increased salience to martial artists as compared to controls. The inverse correlation between amygdala activation and aggressiveness within the martial artist group might be explained by the assumption that the more aggressive martial artists may be more accustomed to violent situations leading to a down-modulation of amygdala activation. Appetitive aggression should be taken into account as a factor contributing to violence., (© 2019 The Authors. Brain and Behavior published by Wiley Periodicals, Inc.)

Infrared spectra of the isolated protonated flavin molecules lumichrome, lumiflavin, riboflavin (vitamin B2), and the biologically important cofactor flavin mononucleotide are measured in the fingerprint region (600-1850 cm(-1)) by means of IR multiple-photon dissociation (IRMPD) spectroscopy. Using density functional theory calculations, the geometries, relative energies, and linear IR absorption spectra of several low-energy isomers are calculated. Comparison of the calculated IR spectra with the measured IRMPD spectra reveals that the N10 substituent on the isoalloxazine ring influences the protonation site of the flavin. Lumichrome, with a hydrogen substituent, is only stable as the N1-protonated tautomer and protonates at N5 of the pyrazine ring. The presence of the ribityl unit in riboflavin leads to protonation at N1 of the pyrimidinedione moiety, and methyl substitution in lumiflavin stabilizes the tautomer that is protonated at O2. In contrast, flavin mononucleotide exists as both the O2- and N1-protonated tautomers. The frequencies and relative intensities of the two C=O stretch vibrations in protonated flavins serve as reliable indicators for their protonation site., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)