New research shows that daily doses of instrumental lullabies can help preterm infants sleep better and feel more comfortable in the NICU, opening the door to innovative care practices that support brain development.
Study: Impact of daily music on comfort scores in preterm infants: a randomized controlled trial. Image Credit: Ratchat / Shutterstock
Scientists at the University Medical Center Utrecht in the Netherlands have conducted a study to explore the impact of music on the comfort, sleep, and physiological stability of preterm infants.
The study is published in the journal Pediatric Research.
Background
Premature birth significantly increases the risk of neurodevelopmental disorders in infants. The stress-inducing sensory environment experienced by infants within clinical settings is believed to be partly responsible for these disorders.
Lack of meaningful sensory inputs, such as the mother’s voice, may hinder sensory-dependent plasticity in preterm infants during their stay in the neonatal intensive care unit. Early sensory experiences, such as low-frequency sounds of the mother's heartbeat and voice, are crucial for healthy brain development. In this context, evidence indicates that fetal brain plasticity is associated with the intrauterine vibroacoustic experience, including low-frequency, regular rhythms of the mother’s heartbeat, voice, and digestive noises.
Infants born prematurely lack the intrauterine vibroacoustic experience; instead, they get exposed to extrauterine, high-frequency stimuli, which can negatively affect their auditory system development.
A growing body of evidence indicates that exposing preterm infants to auditory enrichment interventions, such as music, may benefit sensory processing, brain plasticity, and the regulation of physiological functions.
In this study, scientists have explored whether daily music intervention can improve comfort, reduce sleep disturbances, and stabilize physiological functions in preterm infants in neonatal intensive care units.
Study design
The study was conducted on 56 preterm infants whose gestational age at birth ranged from 29 to 34 weeks. They were randomly assigned to the music intervention group and the placebo group.
Infants belonging to the music intervention group received 8-minute daily exposure to Brahms' Lullaby for up to 15 days. In the placebo group, infants were exposed to silence under identical conditions.
The study measured the effect of music intervention on infants’ comfort, sleep-wake state, and physiological parameters, including heart rate (HR), respiratory rate (RR), and oxygen saturation (SatO2).
Important observations
The baseline characteristics analysis revealed similar comfort levels in both groups before the intervention. The post-intervention analysis showed a significant improvement in comfort level in infants who received music exposure compared to those who did not.
Regarding sleep-wake state, the analysis showed a significantly increased transition from being awake to being asleep in the music intervention group compared to the placebo group. The most frequent transition observed was from a quietly awake state to quiet sleep.
The analysis of physiological parameters revealed no significant changes in heart rate, respiratory rate, and blood oxygen saturation following music exposure.
Study significance
The study finds that infants exposed to recorded instrumental music in neonatal intensive care units exhibit enhanced comfort, increased sleep transitions, and stable physiological parameters.
Existing evidence indicates that music interventions positively impact brain maturation in preterm infants through complex mechanisms. While the exact pathways remain unclear, the findings highlight the potential neuroprotective role of music in neonatal care. The current study findings highlight the need for more comprehensive mechanistic studies to clarify how music can support neurodevelopmental outcomes in premature infants.
The current study finds that infants who were awake before the music exposure tended to fall asleep more frequently after the intervention. The most commonly observed transition was from a quietly awake state to a quiet sleep state. These findings highlight the significance of music interventions in improving the sleep cycle in preterm infants.
The study could not find any significant differences in heart rate, respiratory rate, and blood oxygen saturation between infants who were and were not exposed to music intervention. These results confirm that music can improve comfort and sleep without inducing stress or affecting vital signs.
An instrumental lullaby was used in this study as the music intervention, which helped avoid any possible confounding effects of vocalization and cultural sensitivity, considering the multicultural background of the infants’ parents. These factors collectively helped prevent heterogeneity and increase the generalizability of the study findings. Importantly, the music never exceeded the recommended decibel level of 55 dB, in line with neonatal sensory guidelines.
Besides these positive outcomes, the study has some limitations. As mentioned by the scientists, the study was kept blind from parents and nurses by exposing the infants to music throughout the day. Thus, the scientists could not consider feeding times or recent kangaroo care, which are associated with faster sleep transitions and improved infant blood oxygenation.
Additionally, the alertness scale used in the study, while useful for assessing comfort, was not specifically designed for classifying sleep states. This limitation means the sleep findings should be interpreted cautiously.
The scientists highlight the need for future studies to determine music's more accurate and long-term impact on brain growth, comfort, sleep, and physiological signs of preterm infants. They particularly emphasize utilizing the recently validated Behavioral Sleep Stage Classification for Preterm Infants (BeSSPI) to more accurately determine the sleep-wake state of preterm infants following music exposure.
The scientists are currently working on a project to explore the impact of the same music intervention on structural and functional brain development in preterm infants.