<p>Adequate sleep has a protective effect on an individual’s cognition and behavior. Within social interactions, the engagement in self-protective behaviors is crucial for maintaining a positive self-view. While existing research hints at a link between sleep deprivation and self-protective behaviors through behavioral and neuroimaging studies, there is a lack of conclusive experimental evidence. To address this gap, we conducted a robust reciprocal evaluation task paired with electroencephalography (EEG) to explore self-protective behaviors and their neural correlates in individuals experiencing sleep deprivation following negative social feedback. Our behavioral findings reveal that sleep-deprived individuals are more inclined to reject others’ creative ideas more swiftly and frequently compared to those with regular sleep patterns. The EEG findings highlight various components associated with feedback processing, including frontal P2, P3a, Late Positive Potential (LPP), and parietal P3b. Interestingly, sleep deprivation seems to leave the early encoding of social feedback information, as indicated by the P2 component, unaffected. However, it does influence components linked to feedback processing, such as frontal P3a involved in bottom-up attentional processing, LPP related to sustained attention and processing of motivationally salient stimuli, and early parietal P3b linked to the allocation of attentional resources. These results imply that sleep deprivation could excessively enhance individuals’ bias towards rejection, potentially altering subsequent behaviors by modulating feedback processing pathways. This emphasizes the importance of considering sleep quality in studying social cognition and behavior.</p>