Sleep paralysis in New Zealand tertiary students : prevalence, phenomenology, and associations with sleep quality and psychological distress : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Psychology at Massey University, Manawatū, New Zealand

Abstract

Sleep paralysis (SP) is a transient sleep-wake phenomenon characterised by conscious awareness accompanied by temporary muscle atonia and, often, vivid multisensory hallucinations. Although SP is widely recognised within sleep science and estimated to affect a substantial number of individuals globally, little is known about its prevalence and phenomenology within Aotearoa New Zealand (NZ), particularly among tertiary student populations. Young adulthood is associated with irregular sleep patterns and elevated psychological distress, making tertiary students a population in which SP may be both common and clinically relevant. This study aimed to (1) describe the prevalence of SP among a sample of tertiary students in Aotearoa New Zealand, (2) characterise the main phenomenological features of SP, and (3) examine associations between SP, sleep quality and psychological distress using both qualitative and quantitative analyses. An online survey was administered to 91 NZ tertiary students aged 18-30. SP status was determined using a screening item consistent with core definitional criteria, outlined in current literature, emphasising conscious awareness with muscle atonia. Standardised measures including the Pittsburgh Sleep Quality Index, Generalised Anxiety Disorder-7 and the Depression, Anxiety and Stress Scale were administered to measure sleep quality and psychological distress respectively. Open-ended responses were analysed using content analysis to examine the phenomenological features, and coping strategies of participants. Collectively, the research findings indicated that SP was relatively common within this sample of NZ tertiary students, with 42.9% of participants reporting at least one experience of SP. Psychological distress was also elevated across the sample (DASS-21: M anxiety = 11.4, M depression = 12.7, M stress = 18.3; GAD-7 M = 10.3), while 91.1% of participants met criteria for poor sleep quality based on PSQI scores. Students who reported SP demonstrated significantly higher stress scores than those without SP when SP was examined as a binary (yes/no) variable (U = 617, p = .040). When SP was examined dimensionally using symptom count, a greater number of SP-associated symptoms was significantly associated with higher generalised anxiety (r = .33, p = .043). However, when psychological distress and sleep quality variables were entered simultaneously into a logistic regression model, none were independently associated with SP status and the overall model was not statistically significant (χ² = 10.00, p = .12). Qualitative analysis indicated that SP episodes were commonly characterised by threat-related experiences, including sensed presences, auditory phenomena, and distressing bodily sensations. The integration of quantitative and qualitative findings highlights the importance of emotional context, interpretation, and symptom complexity in shaping distress. This research contributes locally derived prevalence data to an under-research population, extends understanding of the subjective and cultural dimensions of SP, and underscores the relevance of recognising sleep related phenomena within broader discussions of student mental health and psychological wellbeing.