Interaction among subsystems within default mode network diminished in schizophrenia patients: A dynamic connectivity...

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Static functional connectivity analyses have revealed alterations in the default mode network (DMN) in schizophrenia (SZ).
• Limited research exists on the dynamic connectivity characteristics of the DMN in SZ.

Purpose of the Study:

• To compare dynamic functional connectivity within the DMN between individuals with schizophrenia and healthy controls.
• To investigate group differences in DMN connectivity states, dwell times, and transition patterns.

Main Methods:

• Resting-state functional magnetic resonance imaging (fMRI) data from 82 SZ patients and 82 healthy controls (HC).
• Sliding time window method to compute dynamic DMN connectivity.
• K-means clustering to identify functional connectivity states.
• Graph theory metrics to assess time-varying connectivity patterns.

Main Results:

• Healthy controls demonstrated stronger inter-subsystem interaction within the DMN compared to SZ patients.
• SZ patients spent more time in DMN states characterized by sparse connectivity.
• Patients showed weaker connectivity strengths within states, particularly in inter-subsystem connections, and reduced graph metrics.

Conclusions:

• Schizophrenia is associated with impaired dynamic interactions among DMN subsystems, notably involving the PCC, aMPFC, dMPFC, and MTL.
• Reduced DMN integration in SZ may underlie difficulties in self-other distinctions and future-oriented decision-making.