Cognitive Decision-Making Mechanisms in Schizophrenia based on Dynamic Amplitude-Locked Value and Theta-Band Brain Network Analysis.

Schizophrenia is a severe psychiatric disorder that involves disrupted cognition, emotion, and behavior. Growing evidence links its pathophysiology to the impaired coupling of large-scale brain networks. Previous studies have shown that phase synchronization effectively maps functional connectivity in neuronal populations. However, amplitude-based approaches to constructing functional brain networks remain comparatively rare. To address this gap, this study employed the dynamic amplitude-locked value (DALV) method to construct functional connectivity networks from scalp electroencephalogram (EEG) signals and systematically analyzed abnormal neural oscillations of people with schizophrenia (PSZ, N = 46) and healthy controls (HC, N = 31). The experimental results showed that compared with HC: (1) P300 components were significantly elicited at the CPz and FCz electrode sites, with the amplitude markedly reduced in the PSZ. (2) The average power of the whole brain exhibited significantly increased activity in the theta frequency band (p < 0.001) in PSZ and increases within the theta band for the parietal, prefrontal, and left temporal regions. (3) The results of brain network analysis based on DALV showed that there was a significantly reduced node degree, clustering coefficient, local efficiency, and global efficiency of the network in PSZ.