Aberrant Prefrontal–Thalamic–Cerebellar Circuit in Schizophrenia and Depression: Evidence From a Possible Causal Connectivity

Abstract

Neuroimaging studies have suggested the presence of abnormalities in the prefrontal-thalamic-cerebellar circuit in schizophrenia (SCH) and depression (DEP). However, the common and distinct structural and causal connectivity abnormalities in this circuit between the two disorders are still unclear. In the current study, structural and resting-state functional magnetic resonance imaging (fMRI) data were acquired from 20 patients with SCH, 20 depressive patients and 20 healthy controls (HC). Voxel-based morphometry analysis was first used to assess gray matter volume (GMV). Granger causality analysis, seeded at regions with altered GMVs, was subsequently conducted. To discover the differences between the groups, ANCOVA and post hoc tests were performed. Then, the relationships between the structural changes, causal connectivity and clinical variables were investigated. Finally, a leave-one-out resampling method was implemented to test the consistency. Statistical analyses showed the GMV and causal connectivity changes in the prefrontal-thalamic-cerebellar circuit. Compared with HC, both SCH and DEP exhibited decreased GMV in middle frontal gyrus (MFG), and a lower GMV in MFG and medial prefrontal cortex (MPFC) in SCH than DEP. Compared with HC, both patient groups showed increased causal flow from the right cerebellum to the MPFC (common causal connectivity abnormalities). And distinct causal connectivity abnormalities (increased causal connectivity from the left thalamus to the MPFC in SCH than HC and DEP, and increased causal connectivity from the right cerebellum to the left thalamus in DEP than HC and SCH). In addition, the structural deficits in the MPFC and its causal connectivity from the cerebellum were associated with the negative symptom severity in SCH. This study found common/distinct structural deficits and aberrant causal connectivity patterns in the prefrontal-thalamic-cerebellar circuit in SCH and DEP, which may provide a potential direction for understanding the convergent and divergent psychiatric pathological mechanisms between SCH and DEP. Furthermore, concomitant structural and causal connectivity deficits in the MPFC may jointly contribute to the negative symptoms of SCH.

Dynamic changes in thalamic connectivity following stress and its association with future depression severity

“…Increased FC of the thalamus with the DMN and the sensory motor areas and decreased FC with the ECN indicate that, under acute stress, while the information related to self and essential sensory is up‐regulated, executive control signals may exert greater effort in controlling sensory input, and as a result, ECN might down‐regulate thalamus activity. The altered FC changes of the thalamus to the cortical regions especially the dlPFC imply the involvement of the thalamo‐cortical circuit during stress adaption, which is in align with findings in depression (Jiang et al, ; Kang et al, ). Further causality analyses might elucidate the FC changes among different networks.…”

Relationships between abnormal neural activities and cognitive impairments in patients with drug-naive first-episode schizophrenia

“…A partial brain area of right MFG overlapped the medial PFC, and a study on adolescent-onset schizophrenia has also shown that ReHo values in right medial PFC increased [14]. Another study has found that concomitant structural and causal connectivity deficits in medial PFC correlate with the negative symptoms of schizophrenia [54].…”

Altered Default Mode Network Dynamics in Civil Aviation Pilots

“…Neuroimaging has been broadly used in the investigation of the human brain (Jiang et al, 2019a). In particular, restingstate functional magnetic resonance imaging (fMRI) is a very useful technique (Dong et al, 2016;Jiang et al, 2019b).…”