Psychological Determinants of Sleep Paralysis: A Contemporary Review of Anxiety, Stress, and Trauma

Sleep paralysis is a distressing parasomnia marked by temporary immobility during sleep–wake transitions, often accompanied by intense fear and hallucinatory experiences. While traditionally explained through neurophysiological mechanisms, this contemporary review highlights the significant role of psychological factors in shaping both the onset and experience of sleep paralysis episodes. Analysis of recent literature reveals that anxiety is strongly associated with increased episode frequency, heightened fear responses, and anticipatory sleep-related distress. Chronic stress emerges as a key precipitating factor by disrupting sleep continuity and increasing vulnerability to dissociative sleep states. Trauma exposure, particularly unresolved or early-life trauma, is consistently linked to more severe subjective experiences, including vivid fear-based hallucinations, prolonged episodes, and heightened emotional distress. The combined presence of anxiety, stress, and trauma produces a cumulative effect, resulting in greater episode severity and recurrence. These findings support a biopsychosocial understanding of sleep paralysis and underscore the importance of integrating psychological and trauma-informed approaches in assessment and intervention strategies.