The relationship between resting state EEG band aberrations and visual abnormalities in early course psychosis
OA Version
Citation
Abstract
BACKGROUND: Individuals with early course psychosis (ECP) often experience visual disturbances, highlighting the value of better understanding the visual pathway in the disorder. Prior research suggests visual abnormalities are more indicative of future conversion to psychosis compared to auditory distortion or thought disorder. Examining dysfunctional neural activity and connectivity between brain regions can elucidate neural mechanisms underlying these visual abnormalities. This study aims to investigate relationships between self-reported visual abnormalities, electroencephalography (EEG) power, and functional connectivity in ECP. METHODS: 22 healthy controls and 22 ECP participants completed the Audio-Visual-Abnormalities Questionnaire (AVAQ) and the Bonn Visual scale. EEG data was collected during a 5-minute eyes-open resting state session. Fast Fourier Transforms reduced EEG data to 5 frequency bands: Delta, Theta, Alpha, Beta, and Gamma. Group differences in EEG power across diagnosis categories were analyzed with one-way ANOVA and post-hoc t-tests (α = 0.05). Debiased weighted phase lag index (dbWPLI) was used to assess functional connectivity. Pearson correlations correcting for age was performed in R to explore these relationships. Results: Delta power was significantly higher in the ECP group, while no significant power differences were observed in other bands. The total AVAQ and Bonn scores were significantly higher in ECP participants, with ECP scoring significantly higher in the AVAQ visual section. No significant relationships were found between EEG power and questionnaire scores. Significant group differences were observed in gamma-band connectivity, specifically weaker connectivity in the Frontal x Central, Frontal x Left Temporal, Frontal x Right Temporal, Central x R Temporal, and R Temporal x Left Temporal connections. The correlations between these connections, AVAQ, and Bonn scores were not significant.
CONCLUSIONS: Results indicate that ECP participants exhibit aberrations in neural activity, including higher delta power, abnormal gamma-band connectivity, and increased visual abnormalities. No significant associations were found between AVAQ and Bonn Visual scores and EEG power values or connectivity measures, suggesting that these self-reported visual abnormalities may not directly correspond to changes in oscillatory power or connectivity. Future analyses will examine how the age of diagnosis may impact the severity of visual abnormalities in ECP and if other unexamined factors could influence these relationships.
Description
2025
License
Attribution 4.0 International