Manifestation of Sleep Paralysis among Clinical and Non-Clinical Population; A Comparative Study

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Nabeela Raza
Anum Farooq


Background: Sleep paralysis is a transient and often distressing condition characterized by an inability to move or speak during the transition between wakefulness and sleep. Previous studies have highlighted a higher prevalence of sleep paralysis in psychiatric populations compared to the general population, yet comprehensive comparative studies remain scarce. Understanding the nuances of sleep paralysis across different populations is crucial for developing targeted interventions.

Objective: This study aims to compare the manifestation of sleep paralysis among clinical (neurotic and psychotic disorders) and non-clinical populations, with a specific focus on the prevalence of intruder, incubus, and vestibular-motor experiences.

Methods: A comparative cross-sectional design was employed, with a sample size of 90 participants, equally divided among clinical (neurotic and psychotic) and non-clinical groups from Rawalpindi and Islamabad. The study utilized purposive sampling for participant selection. Individuals aged 14 years and above, diagnosed with neurotic disorders, brief psychotic disorder, early psychosis, or those experiencing sleep paralysis without a mental disorder diagnosis were included. The Waterloo Unusual Sleep Experiences Questionnaire-IX (WQ) along with diagnostic scales for depression, anxiety, panic attacks, and psychotic disorders were administered. Data analysis was conducted using IBM SPSS Statistics version 25, employing descriptive statistics, ANOVA, and Chi-Square tests.

Results: The mean age of participants was 22.21 (SD = 4.318). Gender distribution was 54.4% male and 45.6% female. The ANOVA results indicated no significant differences in the intruder and incubus experiences across groups. However, a significant difference was found in the intensity and frequency of vestibular-motor experiences, with F values of 6.684 (p<.01) and 9.231 (p<.01), respectively. Chi-square analysis further highlighted significant differences in the manifestation of sleep paralysis, with vestibular-motor experiences being notably higher among the psychotic group.

Conclusion: The study confirms the higher prevalence of vestibular-motor experiences of sleep paralysis among clinical populations, particularly those with psychotic disorders, compared to non-clinical populations. Intruder and incubus experiences were commonly reported across all groups, indicating a widespread presence of these phenomena regardless of psychiatric diagnosis.

Article Details

How to Cite
Raza, N., & Farooq , A. (2024). Manifestation of Sleep Paralysis among Clinical and Non-Clinical Population; A Comparative Study. Journal of Health and Rehabilitation Research, 4(1), 759–763.
Author Biographies

Nabeela Raza, Riphah International University Pakistan.


Anum Farooq , Shifa Tameer-e-Millat University Islamabad Pakistan

Senior Lecturer, Shifa Tameer-e-Millat University Islamabad Pakistan.


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