Psychiatry Investig.  2025 Apr;22(4):435-441. 10.30773/pi.2024.0354.

Frontal and Parietal Alpha Asymmetry as Biomarkers for Negative Symptoms in Schizophrenia

• Wu YC
• Huang CC
• Wang YG
• Yang CY
• Chang WC
• Chang CC
• Chang HA

• KMID: 2566737
• DOI: http://doi.org/10.30773/pi.2024.0354

Abstract

Objective
Negative symptoms in schizophrenia indicate a poor prognosis. However, the mechanisms underlying the development of negative symptoms remain unclear. This study investigated the relationship between negative symptoms in schizophrenia and frontal alpha asymmetry (FAA).
Methods
The study used a 32-channel electroencephalography to acquire alpha power in 4 target-paired sites in each patient. Regional alpha asymmetry was calculated based on the alpha power using EEGLAB Frontal Alpha Asymmetry Toolbox.
Results
Sixty schizophrenia patients with predominant negative symptoms (PNS), 72 stabilized schizophrenia (SS) patients, and 73 healthy control (HC) participants were enrolled in this study. No significant differences were observed in FAA between the PNS and SS groups, although both groups exhibited reduced P3-P4 alpha asymmetry compared to HCs. A positive correlation was found between F7-F8 alpha asymmetry and illness duration. Additionally, a predictive model based on P3-P4 alpha asymmetry scores was able to differentiate schizophrenia patients from HCs, achieving a sensitivity of 71.2% and a specificity of 72.6%.
Conclusion
This study highlighted that parietal alpha asymmetry could serve as a valuable diagnostic tool for schizophrenia.

Keyword

Schizophrenia; Negative symptoms; EEG; Functional laterality; Alpha rhythm