Cortical network analysis in patients affected by schizophrenia.

Area of Science:

• Neuroscience
• Psychiatry
• Brain Imaging

Background:

• Schizophrenia (SCHZ) is a complex mental disorder affecting cognitive functions.
• Understanding brain functional network alterations is crucial for SCHZ research.
• Working memory tasks are often impaired in individuals with SCHZ.

Purpose of the Study:

• To investigate structural changes in brain functional networks in SCHZ patients.
• To compare network alterations during a 2-back working memory task versus rest.
• To identify specific frequency bands and brain regions involved in these changes.

Main Methods:

• Utilized high-resolution electroencephalography (EEG) to obtain cortical signals.
• Employed realistic head models and linear inverse solutions for signal analysis.
• Estimated functional networks using spectral coherence and graph theory metrics (density, node degree).

Main Results:

• Significant differences in cortical functional networks were observed in the Alpha2 frequency band (11-13 Hz) between SCHZ patients and controls.
• SCHZ networks showed radical structural alterations during the memory task, with increased deviations from the resting state compared to controls.
• A compensatory mechanism was identified in SCHZ patients performing the task correctly, characterized by frontal asymmetry (higher left frontal lobe activation) in the Alpha2 band.

Conclusions:

• Brain functional network structure, particularly in the Alpha2 band, is significantly disrupted in schizophrenia.
• These disruptions are exacerbated during working memory tasks, suggesting a role in cognitive deficits.
• Compensatory mechanisms involving frontal lobe activation may aid in task performance despite network alterations.