The effect of hypervigilance on visual working memory in insomnia disorder: Evidence from ERP study

This study investigates the impact of hypervigilance on visual working memory in individuals with insomnia disorder using event-related potentials (ERP) and time-frequency analysis.

A total of 45 insomnia disorder (ID) patients and 43 healthy controls (HC) participated in a visual working memory task that involved encoding, maintaining, and retrieving visual stimuli (S1 and S2) of blurred and clear pictures. ERP components and frequency bands were analyzed across these stages.

The ID group had significantly altered ERP amplitudes and increased theta and beta activity across all stages compared to the HC group, indicating hypervigilance and cognitive resource consumption during working memory processing. In the encoding stage, P100 and N170 amplitudes were significantly correlated with insomnia severity (ISI), while P200 amplitude was linked to HAMA score. During the maintenance stage, CNV amplitude and increased theta power were associated with sustained attention, which correlated with ISI scores, reflecting the burden of maintaining attention in hypervigilance states. In the retrieval stage, the ID group showed reduced P300 amplitudes but increased LPC amplitudes, highlighting their struggle with memory updating and complex cognitive processing under hypervigilance states.

These findings suggest that ID patients exhibit hypervigilance, which affects the efficiency of visual working memory, impairs attention regulation, and increases cognitive load during tasks. Understanding these mechanisms may provide insights for clinical interventions aimed at improving cognitive function in ID patients.