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Background: Thalamocortical circuit imbalance characterized by prefronto-thalamic hypoconnectivity and sensorimotor-thalamic hyperconnectivity has been consistently documented at rest in schizophrenia (SCZ). However, this thalamocortical imbalance has not been studied during task engagement to date, limiting our understanding of its role in cognitive dysfunction in schizophrenia., Methods: Both n-back working memory (WM) task-fMRI and resting-state fMRI data were collected from 172 patients with SCZ and 103 healthy control subjects (HC). A replication sample with 49 SCZ and 48 HC was independently obtained. Sixteen thalamic subdivisions were employed as seeds for the analysis., Results: During both task-performance and rest, SCZ showed thalamic hyperconnectivity with sensorimotor cortices, but hypoconnectivity with prefrontal-cerebellar regions relative to controls. Higher sensorimotor-thalamic connectivity and lower prefronto-thalamic connectivity both relate to poorer WM performance (lower task accuracy and longer response time) and difficulties in discriminating target from nontarget (lower d' score) in n-back task. The prefronto-thalamic hypoconnectivity and sensorimotor-thalamic hyperconnectivity were anti-correlated both in SCZ and HCs; this anti-correlation was more pronounced with less cognitive demand (rest>0-back>2-back). These findings replicated well in the second sample. Finally, the hypo- and hyper-connectivity patterns during resting-state positively correlated with the hypo- and hyper-connectivity during 2-back task-state in SCZ respectively., Conclusions: The thalamocortical imbalance reflected by prefronto-thalamic hypoconnectivity and sensorimotor-thalamic hyperconnectivity is present both at rest and during task engagement in SCZ and relates to working memory performance. The frontal reduction, sensorimotor enhancement pattern of thalamocortical imbalance is a state-invariant feature of SCZ that affects a core cognitive function., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center.All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: Schizophrenia (SZ) and bipolar I disorder (BD) share many overlapping clinical features, confounding the current diagnostic systems. Recent studies suggest the posterior cingulate (PCC) and medial prefrontal (MPFC) cortices that are involved in SZ and BD pathophysiology. However, the roles of PCC and MPFC in providing specific distinctive and shared neural substrates between these two disorders remain largely unknown. Examining the neurophysiologic mechanism of these diseases may help explain the clinical observations and differentiate the two disorders., Methods: We used the Dynamic Casual Modeling (DCM), which is capable of eliciting hidden neuronal dynamics and reveal cross-regulation of multiple neuronal systems, to characterize the pattern of disrupted effective connectivity in the left PCC-MPFC circuit during working memory tasks in 36 SZ and 20 BD patients as well as 29 healthy controls., Results: Compared to the healthy controls, both SZ and BD patient groups exhibited significant negative effective connectivity from the left MPFC to PCC. The negative effective connectivity was more remarkable in schizophrenic patients. Only patients with BD differed from healthy controls with positive effective connectivity from the left PCC to MPFC., Conclusions: Whole brain analysis revealed deactivation of the left PCC and MPFC across all patient groups. This study provides new insight that changes in effective connectivity of the left MPFC to left PCC circuit during working memory processing may be a core pathophysiological feature distinguishing SZ from BD., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Objective: Although studies have demonstrated the involvement of the nucleus accumbens (NAc) in the neurobiology of eating disorders, its alterations in bulimia nervosa (BN) remain largely unknown. This study investigated the structural and functional properties of NAc in patients with BN. Method: Based on the resting‐state functional MRI and high‐resolution anatomical T1‐weighted imaging data acquired from 43 right‐handed BN patients and 40 sex‐, age‐ and education‐matched right‐handed healthy controls (HCs), the group differences in gray matter volume (GMV) and fractional amplitude of low‐frequency fluctuation (fALFF) in slow‐4 and ‐5 bands and functional connectivity (FC) of NAc subregions (core and shell) were compared. The relationships between MRI and clinical data were explored in the BN group. Results: Compared with HCs, BN patients showed preserved GMV, decreased fALFF in slow‐5 band of the left NAc core and shell, decreased FC between left NAc core and right caudate, and increased FC between all NAc subregions and frontal regions, between all NAc subregions (except the right NAc core) and the supramarginal gyrus (SMG), and between right NAc shell and left middle temporal gyrus. FC between the NAc and SMG was correlated with emotional eating behaviors. Discussion: Our study revealed preserved GMV, local neuronal activity reduction and functional network reorganization of the NAc in BN. The functional network reorganization of the NAc mainly occurred in the frontal cortex and was correlated with emotional eating behavior. These findings may provide novel insights into the BN using NAc as an entry point. Public significance: Although studies have demonstrated the involvement of the nucleus accumbens (NAc) in the neurobiology of eating disorders, its alterations in bulimia nervosa (BN) remain largely unknown. We used a multimodal MRI technique to systematically investigate structural and functional alterations in NAc subregions of BN patients and explored the associations between such alterations and maladaptive eating behaviors, hoping to provide novel insights into BN. [ABSTRACT FROM AUTHOR]

Self-face recognition is a vital aspect of self-referential processing, which is closely related to affective states. However, neuroimaging research on self-face recognition in adults with major depressive disorder is lacking. This study aims to investigate the alteration of brain activation during self-face recognition in adults with first-episode major depressive disorder (FEMDD) via functional magnetic resonance imaging (fMRI); FEMDD (n = 59) and healthy controls (HC, n = 36) who performed a self-face-recognition task during the fMRI scan. The differences in brain activation signal values between the two groups were analyzed, and Pearson correlation analysis was used to evaluate the relationship between the brain activation of significant group differences and the severity of depressive symptoms and negative self-evaluation; FEMDD showed significantly decreased brain activation in the bilateral occipital cortex, bilateral fusiform gyrus, right inferior frontal gyrus, and right insula during the task compared with HC. No significant correlation was detected between brain activation with significant group differences and the severity of depression and negative self-evaluation in FEMDD or HC. The results suggest the involvement of the malfunctioning visual cortex, prefrontal cortex, and insula in the pathophysiology of self-face recognition in FEMDD, which may provide a novel therapeutic target for adults with FEMDD. [ABSTRACT FROM AUTHOR]

Alcohol dependence (AD) is a chronic and relapsing disorder. Conditioned cues associated with the rewarding properties of drugs could trigger motivational/physiological reactions and render subjects vulnerable to relapse. Striatal circuit dysfunction has been implicated in alcohol addiction behaviours. However, little is known about the striatal tracts structural connectivity changes underlying cue induced reactivity in AD. In our present study, we recruited 51 patients with AD; 31 individuals had physiological response. We used seed‐based classification by probabilistic tractography with nine target masks to explore the white matter integrity of striatal circuits in physiological responders (N = 31), non‐responders (N = 20), and healthy controls (N = 27). Compared with healthy controls, physiological responders showed lower fractional anisotropy (FA) and/or higher mean diffusivity in the striatum‐dorsolateral prefrontal cortex (dlPFC), striatum‐ventral lateral prefrontal cortex, striatum‐supplementary motor area (SMA), and striatum‐insular. Considering age and smoking are potential nuisances to diffusion parameters, an analysis of covariance also was conducted and similar results were found. We also found the cue‐induced physiological response was negatively associated with the FA of the striatum‐SMA (r = −0.287; p = 0.045) and left striatum‐dlPFC (r = −0.253; p = 0.079) in AD. In our study, we found abnormal integrity of striatal circuit structural connectivity in AD with physiological cue reactivity, especially trajectory from prefrontal cortex and insular. We also found the FA of striatal tracks was negatively associated with the degree of cue reactivity. Our findings provide further evidence for reduced white matter integrity of striatal circuits for cue reactivity in male individuals with AD. [ABSTRACT FROM AUTHOR]

According to the Unaccusative Hypothesis, intransitive verbs are divided into unaccusative and unergative ones based on the distinction of their syntactic properties, which has been proved by previous theoretical and empirical evidence. However, debate has been raised regarding whether intransitive verbs in Mandarin Chinese can be split into unaccusative and unergative ones syntactically. To analyze this theoretical controversy, the present study employed functional magnetic resonance imaging to compare the neural processing of deep unaccusative, unergative sentences, and passive sentences (derived structures undergoing a syntactic movement) in Mandarin Chinese. The results revealed no significant difference in the neural processing of deep unaccusative and unergative sentences, and the comparisons between passive sentences and the other sentence types revealed activation in the left superior temporal gyrus (LSTG) and the left middle frontal gyrus (LMFG). These findings indicate that the syntactic processing of unaccusative and unergative verbs in Mandarin Chinese is highly similar but different from that of passive verbs, which suggests that deep unaccusative and unergative sentences in Mandarin Chinese are both base-generated structures and that there is no syntactic distinction between unaccusative and unergative verbs in Mandarin Chinese. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess brain functional alterations in BN patients with affective disorders and their association with maladaptive eating behaviors. A total of 42 BN patients with affective disorders (anxiety and depression) and 47 healthy controls (HCs) were enrolled in this study. The resting-state fMRI data were analyzed for functional changes as indicated by regional homogeneity based on Kendall's coefficient of concordance (KCC-ReHo) and seed-based functional connectivity (FC). A principal component analysis (PCA) model was used to identify the commonalities within the behavioral questionnaires from the BN group. Patients in the BN group showed decreased ReHo in the bilateral middle frontal gyrus (MFG) and right supramarginal gyrus (SMG). Additionally, the BN group showed increased FC between the left MFG and the right inferior temporal gyrus (ITG); decreased FC between the right MFG and the bilateral insula and the left middle temporal gyrus (MTG); and decreased FC between the right SMG and the left superior temporal gyrus (STG) and right inferior frontal gyrus (IFG). In the FC-behavior association analysis, the second principal component (PC2) was negatively correlated with FC between the left MFG and the right ITG. Based on a brain functional analysis (ReHo and FC), this study revealed significant aberrant changes in the frontal-temporal regions of BN patients with affective disorders. These regions, which serve as fronto-temporal circuitry, are associated with restraint and emotional eating behaviors. Our findings shed new light on the neural mechanisms underlying the condition. • Anxiety and depression are the most common affective comorbidities in patients with bulimia nervosa • Little is known about the neuropathic mechanisms underlying comorbid affective disorders in bulimia nervosa • Potential disturbance in the recruitment of fronto-temporal circuitry in BN patients with comorbid affective disorders • The brain functional changes were correlated with disordered eating behaviors • Interplay between BN-specific and comorbid psychopathological effects may contribute to specific brain functional activity [ABSTRACT FROM AUTHOR]

In the last two decades there has been an increase on task and resting-state functional Magnetic Resonance Imaging (fMRI) studies that explore the brain's functional changes in schizophrenia. However, it remains unclear as to whether the brain's functional changes during the resting state are sensitive to the same brain regions during task fMRI. Therefore, we conducted a systematic literature search of task and resting-state fMRI studies that investigated brain pathological changes in first-episode schizophrenia (Fleischhacker et al.). Nineteen studies met the inclusion criteria; seven were resting state fMRI studies with 371 FES patients and 363 healthy controls and twelve were task fMRI studies with 235 FES patients and 291 healthy controls. We found overlapping task and resting-state fMRI abnormalities in the prefrontal regions, including the dorsal lateral prefrontal cortex, the orbital frontal cortex and the temporal lobe, especially in the left superior temporal gyrus (STG). The findings of this systematic review support the frontotemporal hypothesis of schizophrenia, and the disruption in prefrontal and STG might represent the pathophysiology of schizophrenia disorder at a relatively early stage. [ABSTRACT FROM AUTHOR]