Related Experiment Video
Updated: Mar 10, 2026
How to Obtain Reliable Visual Event-related Potentials in Newborns
Published on: October 24, 2019
Effects of Cycled Lighting Versus Continuous Near Darkness on Physiological Stability and Motor Activity Level in
Valérie Lebel1, Marilyn Aita, Celeste Johnston
1Faculty of Nursing, University of Montreal, Québec, Canada (Drs Lebel, Aita, Héon, and Dupuis); and Faculty of Nursing, McGill University, Montreal, Québec, Canada (Dr Johnston).
Insights
Neither cycled lighting nor continuous near darkness impacted preterm infants' stability or activity. Further research is needed to determine the optimal lighting strategy for these vulnerable newborns.
Area of Science:
- Neonatal Intensive Care Unit (NICU) environment optimization
- Developmental pediatrics and infant care
- Clinical trial methodology in neonatology
Background:
- Preterm infants in NICUs experience fluctuating and high light intensities, potentially causing physiological instability and increased motor activity.
- Existing research on lighting control methods, specifically cycled lighting and continuous near darkness, has yielded ambivalent results.
- The optimal lighting strategy for preterm infants remains undetermined, necessitating further investigation.
Purpose of the Study:
- To compare the effects of cycled lighting versus continuous near darkness on preterm infants.
- To assess the impact of these lighting conditions on physiological stability and motor activity levels.
- To provide evidence for optimizing the NICU environment for infants born between 28 and 32 weeks of gestation.
Main Methods:
- A randomized clinical trial involving 38 preterm infants (28-32 weeks gestation) was conducted.
- Infants were randomly assigned to either cycled lighting or continuous near darkness for 24 hours.
- Physiological stability was assessed using the Stability of the Cardiorespiratory System in Premature Infants (SCRIP) score, means, and coefficient of variation; motor activity was measured using an accelerometer.
Main Results:
- No significant differences were observed between the cycled lighting and continuous near darkness groups.
- Both lighting conditions resulted in comparable physiological stability, as measured by SCRIP scores and variability.
- Motor activity levels were also similar between the two groups, indicating no adverse effects from either lighting method.
Conclusions:
- Neither cycled lighting nor continuous near darkness demonstrated negative impacts on the physiological stability or motor activity of preterm infants.
- Both lighting strategies appear to be safe for short-term use in this population.
- Further research is essential to identify the most appropriate lighting control method for preterm infants within this gestational age range.
Background:
Preterm infants generally spend weeks in the neonatal intensive care unit where light intensity can fluctuate as well as be high, leading to physiological instability and increased motor activity in these infants. To date, 2 lighting control methods have been studied: cycled lighting and continuous near darkness. The most appropriate method of lighting is still unknown due to ambivalent results from the studies that have assessed these 2 interventions.
Objective:
To compare the effects of cycled lighting versus continuous near darkness on physiological stability and motor activity level in preterm infants born between 28 and 32 weeks of gestation.
Methods:
A randomized clinical trial was conducted to compare physiological stability and motor activity level in preterm infants assigned to cycled lighting or continuous near darkness. Thirty-eight participants were recruited and randomly assigned to one of the lighting conditions for 24 hours. Physiological stability was measured using the Stability of the Cardiorespiratory System in Premature Infants (SCRIP) score, the means, and the coefficient of variation of each physiological parameter measured. The level of motor activity was measured with an accelerometer.
Results:
There were no significant differences between the 2 groups with regard to physiological stability measured by the SCRIP score, means, and coefficient of variation as well as motor activity level. Participants in both groups were physiologically stable and their motor activity level was comparable.
Implications For Practice And Research:
Neither cycled lighting nor continuous near darkness negatively impacted infant's physiologic stability and motor activity level. Further research is required to identify the most appropriate lighting control method for preterm infants born between 28 and 32 weeks of gestation.
