Parietal Alpha-ERD and Theta-ERS Serve as Neuroelectrical Indices for Working Memory Impairment Following Total Sleep Deprivation

Abstract

Highlights: What are the main findings? A 36 h duration of TSD significantly impairs verbal working memory accuracy and reaction time. TSD induces abnormal enhancements of parietal alpha-ERD/theta-ERS and suppressed N2/P3 amplitudes. What are the implications of the main findings? Enhanced parietal ERD/ERS reflects an inefficient neural compensatory mechanism under fatigue. Parietal electrophysiological indices serve as reliable biomarkers for sleep loss-induced working memory impairment. Background/Objectives: Acute total sleep deprivation (TSD) is known to impair working memory capacity. However, the specific relationship between alterations in the brain’s electrical power spectrum following TSD and working memory deficits remains poorly understood. Methods: In this study, 30 healthy young adults (14 males and 16 females) were enrolled, and 28 participants were finally included in the analysis after excluding EEG data with excessive noise, who underwent a verbal working memory task under two conditions: baseline sleep (BL) and 36 h of TSD. EEG data were recorded concurrently. Results: We observed a significant decrease in working memory accuracy and a significant prolongation of reaction time after TSD. Furthermore, TSD led to a significant enhancement of parietal alpha-ERD (at electrodes P3/Pz/P4) and theta-ERS, accompanied by a reduction in N2 and P3 wave amplitudes. Conclusions: These findings suggest that TSD may impair working memory by weakening parietal alpha-ERD and early conflict monitoring and late attention evaluation processes. The enhanced theta-ERS might represent a compensatory mechanism.