Abnormal cortico-limbic connectivity during emotional processing correlates with symptom severity in schizophrenia

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Science

Background:

• Impaired emotional processing is a hallmark of schizophrenia (SZ).
• Abnormalities in SZ are linked to disrupted fronto-limbic circuitry integrity.
• Effective connectivity in SZ emotional circuitry remains under-explored.

Purpose of the Study:

• To investigate effective connectivity within the emotional circuitry during implicit affective stimulus processing in SZ.
• To characterize causal relationships between brain regions involved in emotional processing in SZ.

Main Methods:

• Functional magnetic resonance imaging (fMRI) and Dynamic Causal Modeling (DCM) were employed.
• Connectivity was modeled between amygdala (Amy), DLPFC, VPFC, FG, and VC.
• Bayesian Model Selection and averaging determined the optimal network model.

Main Results:

• SZ patients exhibited reduced DLPFC to Amy connectivity.
• Increased Amy to VPFC connectivity was observed in SZ.
• SZ showed decreased driving input to Amy for affective stimuli.
• DLPFC to Amy connectivity correlated with psychopathology severity.

Conclusions:

• Findings suggest functional disconnection in brain networks contributing to SZ symptoms.
• Effective connectivity in cortico-limbic structures may serve as a marker for SZ severity and treatment response.