Shared and Disorder-Specific Alterations of Brain Temporal Dynamics in Obsessive-Compulsive Disorder and Schizophrenia

Abstract

Background: Obsessive-compulsive disorder (OCD) and schizophrenia have distinct but also overlapping symptoms. Few studies have examined the shared and disorder-specific disturbances in dynamic brain function in the 2 disorders.

Study design: Resting-state functional magnetic resonance imaging data of 31 patients with OCD and 49 patients with schizophrenia, all untreated, and 45 healthy controls (HCs) were analyzed using spatial group independent component (IC) analysis. Time-varying degree centrality patterns across the whole brain were clustered into 3 reoccurring states, and state transition metrics were obtained. We further explored regional temporal variability of degree centrality for each IC across all time windows.

Study results: Patients with OCD and patients with schizophrenia both showed decreased occurrence of a state having the highest centrality in the sensorimotor and auditory networks. Additionally, patients with OCD and patients with schizophrenia both exhibited reduced dynamics of degree centrality in the superior frontal gyrus than controls, while dynamic degree centrality of the cerebellum was lower in patients with schizophrenia than with OCD and HCs. Altered dynamics of degree centrality nominally correlated with symptom severity in both patient groups.

Conclusions: Our study provides evidence of transdiagnostic and clinically relevant functional brain abnormalities across OCD and schizophrenia in neocortex, as well as functional dynamic alterations in the cerebellum specific to schizophrenia. These findings add to the recognition of overlap in neocortical alterations in the 2 disorders, and indicate that cerebellar alterations in schizophrenia may be specifically important in schizophrenia pathophysiology via impact on cerebellar thalamocortical circuitry.

Keywords: brain; degree centrality; obsessive-compulsive disorder; resting-state functional magnetic resonance imaging; schizophrenia; temporal dynamics.

Fig. 1.

The 55 independent components (ICs) derived from all subjects in the present study were divided into 8 functional networks: Auditory network (AUD), default mode network (DMN), executive control network (ECN), language network (LAN), salience network (SAN), subcortical network (SC), sensorimotor network (SMN), and visual network.

Fig. 2.

Cluster centroids of time-varying degree centrality patterns in all subjects (A). The radar map of mean degree centrality of each network for 3 states (B). Cluster centroids of time-varying degree centrality patterns in obsessive-compulsive disorder (OCD), schizophrenia (SZ), and healthy controls (HC), respectively (C). Abbreviations of brain networks see figure 1.

Fig. 3.

Group comparisons of state transition metrics. Patients with obsessive-compulsive disorder (OCD) showed decreased fractional time in state 3 compared with healthy controls (HC) (A). Patients with OCD and schizophrenia (SZ) both showed decreased dwell time in state 3 compared with HC (B). No significant group difference in number of transitions (C). The * represents uncorrected P < .05, and the ** represents corrected P < .05.

Fig. 4.

Group comparisons of temporal variability of degree centrality (A). Spatial maps of independent component (IC) 38 and IC76 (B). Significant correlations between temporal variability of degree centrality for IC38 and obsessive-compulsive score in patients with obsessive-compulsive disorder (OCD) (C). Significant correlation between temporal variability of degree centrality for IC76 and positive symptom score of Positive and Negative Syndrome Scale (PANSS) in schizophrenia (SZ) (D). The * represents uncorrected P < .05, and the ** represents corrected P < .05.