Related Experiment Video
Updated: Feb 17, 2026

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments
Published on: August 8, 2019
Assessing Sleep Architecture in Rural Eastern Cape Villagers of South Africa Using ŌURA Ring Data
Erica Kilius1,2, Ming Fei Li2, David R Samson3
1Department of Anthropology, University of Northern British Columbia, Prince George, British Columbia, Canada.
Objectives:
To examine the sleep architecture (proportion of Light, Rapid Eye Movement (REM), and Deep Sleep) of rural villagers using noninvasive, wearable ŌURA rings.
Methods:
From June to August 2023, we collected sleep data from 30 participants (16 men, 14 women, 370 nights) using ŌURA rings. Regression models were used to investigate the effect of gender, age, household size, livestock presence, and temperature on sleep patterns and sleep architecture.
Results:
Average Total Sleep Time (TST) in the community was 7.6 h (SD: 1.01). Average proportion (%) Light Sleep was 59.9%, % REM Sleep was 17.9%, and % Deep Sleep was 22.2%. Men who cared for livestock had significantly higher % Light Sleep and lower % REM sleep compared to men who did not have livestock. Presence of livestock did not significantly affect men or women's % Deep Sleep. Temperature was positively associated with % Light and negatively associated with % REM and % Deep Sleep.
Conclusions:
We found that men who were responsible for livestock tended to have more % Light Sleep and less % REM Sleep than men without livestock. Livestock presence did not affect women's % Light or REM sleep stages, and % Deep Sleep remained unchanged between groups. Temperature was associated with changes in all sleep stages. Our findings highlight the need for naturalistic studies investigating sleep architecture in non-industrialized settings.
Related Concept Videos
Substance Use Disorders Affecting Sleep
Understanding the concepts of physical dependence,...
Sleep Apnea
The condition is more prevalent among...
Understanding Sleep
The circadian rhythm, a nearly 24-hour cycle, is deeply influenced by environmental light cues. Light exposure directly affects the hypothalamus, which in turn regulates...
Sleep-Wake Cycles
NREM Sleep
NREM sleep comprises four progressive stages that seamlessly merge:
Assessment of apical radial pulse
The A-R pulse assessment involves simultaneous evaluation of the apical and radial pulses. When the apical and radial pulse rates vary, this assessment helps identify a pulse deficit.
Pre-Procedural Preparation
Insufficient Sleep and Sleep Deprivation
Sleep deprivation is a more severe form of sleep loss...

