Sound based multisensory interventions for sleep: A scoping review

Sleep disorders are highly prevalent and clinically significant. According to the Centers for Disease Control and Prevention (CDC), more than one-third of adults in the United States experience insufficient sleep. Insomnia is one of the most common sleep disorders, with epidemiological research showing that about 30 % of adults report insomnia symptoms annually and 6 % – 10 % meet criteria for chronic insomnia. Limitations of traditional treatments highlight the need for accessible and effective alternatives. Sound based multisensory interventions, which can influence neural activity, offer promising strategies for improving sleep quality. This scoping review examined their characteristics and mechanisms to provide foundational evidence for developing practical sleep interventions. A search of Scopus, Web of Science, and PubMed identified studies published between January 2014 and April 2024, with eligibility determined using Population–Concept–Context (PCC) criteria. From 576 retrieved articles, 17 met the inclusion criteria. Interventions were categorized by sensory combinations, with descriptive summaries of study characteristics and thematic analysis of the functional roles of sound in sleep. The included studies were conducted in home, hospital, and laboratory settings and involved participants with and without insomnia, with sample sizes ranging from 9 to 85. All interventions incorporated auditory stimuli with combinations of visual, tactile, and olfactory elements. Auditory–visual pairings were most common, followed by auditory–tactile combinations. Functional roles of sound included brainwave synchronization, relaxation, emotional regulation, and noise masking, contributing to improvements in sleep. This review highlights the therapeutic potential of sound-based multisensory interventions and underscores the need for future research to refine sensory combinations and evaluate long-term effects across diverse populations.