The link between Dark Triad personality traits and sleep quality: a meta-analysis

This research project consists of a systematic review and meta-analysis designed to map the circadian and restorative architecture of the Dark Triad by synthesizing its relationship with Sleep Quality. While Machiavellianism, Narcissism, and Psychopathy are primarily defined by their interpersonal and behavioral "darkness," their impact on the fundamental biological necessity of sleep remains inconsistent in the literature. The primary purpose of this work is to bridge the gap between personality profiles and sleep physiology, specifically addressing whether these traits are underpinned by a genuine deficit in sleep architecture or a psychological interference driven by nocturnal preference and pre-sleep arousal. By moving beyond simple correlations, this project evaluates the socio-biological synchronization of these traits, investigating how the "dark" personality core functions within the constraints of social jetlag and circadian demands. Key moderators, such as the use of subjective vs. objective metrics (PSQI vs. Actigraphy), the impact of eveningness chronotypes, and the role of sex and age, will be rigorously analyzed to explain the high variance in current findings. The anticipated result is a clear characterization of the nocturnal profile associated with the Dark Triad, identifying whether sleep impairment is a stable phenotypic cost or a secondary consequence of circadian preference. By establishing the somatic burden of these traits, this study will clarify the relationship between "dark" personality structures and the physiological capacity for nocturnal restoration.