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Schizophrenia is a complex mental disorder with disorganized communication among large-scale brain networks, as demonstrated by impaired resting-state functional connectivity (rsFC). Individual rsFC studies, however, vary greatly in their methods and findings. We searched for consistent patterns of network dysfunction in schizophrenia by using a coordinate-based meta-analysis. Fifty-six seed-based voxel-wise rsFC datasets from 52 publications (2115 patients and 2297 healthy controls) were included in this meta-analysis. Then, coordinates of seed regions of interest (ROI) and between-group effects were extracted and coded. Seed ROIs were categorized into seed networks by their location within an a priori template. Multilevel kernel density analysis was used to identify brain networks in which schizophrenia was linked to hyper-connectivity or hypo-connectivity with each a priori network. Our results showed that schizophrenia was characterized by hypoconnectivity within the default network (DN, self-related thought), affective network (AN, emotion processing), ventral attention network (VAN, processing of salience), thalamus network (TN, gating information) and somatosensory network (SS, involved in sensory and auditory perception). Additionally, hypo-connectivity between the VAN and TN, VAN and DN, VAN and frontoparietal network (FN, external goal-directed regulation), FN and TN, and FN and DN were found in schizophrenia. Finally, the only instance of hyper-connectivity in schizophrenia was observed between the AN and VAN. Our meta-analysis motivates an empirical foundation for a disconnected large-scale brain networks model of schizophrenia in which the salience processing network (VAN) plays the core role, and its imbalanced communication with other functional networks may underlie the core difficulty of patients to differentiate self-representation (inner world) and environmental salience processing (outside world). [ABSTRACT FROM AUTHOR]

Purpose: The present study aims to investigate structural and functional connectivity (SC and FC) in cerebello-cerebral circuit in idiopathic generalized epilepsy (IGE).Methods: Diffusion tensor imaging and resting-state imaging data were collected from 57 patients with IGE and 66 controls in the present study. First, we performed bidirectional probabilistic fiber tracking between cerebellum and cerebral cortex, consisting of cerebellar efferent and afferent fibers. Then, strength of structural connectivity (SCS), fractional anisotropy (FA), mean diffusivity (MD), and radial diffusivity (RD) were extracted and compared between groups. Finally, cerebellar FC with cerebral cortex was evaluated with seeding at dentate nucleus. Between-group comparisons were performed using t tests with a significant level setting at p < 0.05 with threshold-free cluster enhancement correction.Results: The patients with IGE showed decreased SCS in cerebellar efferent fibers to sensorimotor cortex in anterior corona radiate and increased SCS in efferent fibers to occipital cortex in posterior corona radiata. The SCS in cerebellar afferent fibers in corticospinal tract from frontal and in retrolenticular part of the internal capsule from occipital cortices were increased in IGE, and SCS in afferent fibers in posterior limb of internal capsule from parietal cortex was decreased. Decreased FA and increased MD and RD were observed in cerebello-cerebral tracts. Besides, decreased cerebellar FC with putamen and motor cortex was observed in IGE.Conclusion: The patients with IGE demonstrated distinct alterations in efferent and afferent pathways between cerebellum and different cerebral cortices, which might be the pathological anatomical basis for cerebellar modulation effect on epileptic activities and contribute to motor deficits.Key Points: • IGE showed decreased SCS in cerebellar efferent fibers to the sensorimotor cortex and increased SCS in efferent fibers to the occipital cortex. • Patients demonstrated increased SCS in cerebellar afferent fibers from the frontal and the occipital cortex and decreased SCS in afferent fibers from parietal cortex. • Decreased FC between motor-related regions and dentate nucleus was observed in IGE. [ABSTRACT FROM AUTHOR]