Broadband Sound Administration Improves Sleep Onset Latency in Healthy Subjects in a Model of Transient Insomnia

Effects of broadband music and audible band music on relaxation states and cognitive function in young adults: a randomized controlled trial

BACKGROUND

Although broadband music with inaudible high-frequency components may benefit human well-being, this research area is largely unexplored and lacks sufficient studies on the topic. This study aimed to investigate and compare the effects of broadband and audible band music on relaxation states and cognitive function in young adults.

METHODS

A single-blind randomized controlled trial was conducted in a professional soundproof laboratory from December 22, 2022, to January 18, 2023 with 32 participants randomly assigned to two groups, "Day 1 broadband + Day 2 audible band" (n = 16) and "Day 1 audible band + Day 2 broadband" (n = 16), listening to either broadband or audible band music (the same music piece played on the piano and harp) for two sessions of 15 min each on two consecutive days. Cognitive function was measured using CNS Vital Signs at pre-listening, after the 1st session, and after the 2nd session, while heart rate was monitored throughout the experiment. Visual Analog Scale was also administered for self-reported arousal, stress, thinking ability, and attention following each listening session.

RESULTS

No significant differences were found in heart rate, cognitive flexibility, and executive function between the broadband listening group and the audible band-listening group (p > 0.05). However, the broadband group exhibited significant differences in mean heart rate at several time points, as well as a significant improvement in VAS stress level during the 2nd listening session compared to the 1st (p < 0.05). On the other hand, significant improvements in cognitive flexibility and executive function were observed in the audible band group across different time points (p < 0.05).

CONCLUSION

Comparative analysis showed that broadband and audible band music influenced cognitive function differently. Short-term audible band music listening significantly improved cognitive flexibility and executive function, while short-term broadband music listening significantly reduced reaction time in cognitive tests. Additionally, broadband music consistently resulted in lower mean heart rates compared to audible band music at all time points, suggesting that it may be more effective in promoting relaxation and reducing stress, although these differences were not statistically significant. Since the cognitive enhancing effects of broadband music may be counteracted by the drowsy effect of the selected relaxing music, using different types of music may be necessary to confirm its effects in future studies.

Effect of sleep ambient music on sleep quality and mental health in college students: a self-controlled study

To verify the effect of sleep ambient music intervention (SAMI) on sleep quality and mental status of college students, and to further explore the minimum effective duration of SAMI, this study was designed as a pre-and post-intervention self-controlled exploratory study. Participants were subjected to a one-week no-intervention test, then 4 weeks of music intervention followed. Subjective sleep quality data were collected using the Pittsburgh Sleep Quality Index (PSQI); objective sleep quality data were collected with Actigraphy; and mental status data were collected using the State-Trait Anxiety Inventory (STAI) and the Beck Depression Inventory-II (BDI-II). Data were analyzed and processed using mixed-effects models and repeated measures. The results showed that compared with the no-intervention week, college students' subjective sleep quality, objective sleep onset latency (SOL), trait anxiety, and depression symptom were reduced at week 1; week 2; week 3; week 4 under SAMI; state anxiety of college students at week 3 and week 4 under SAMI were also reduced. And there were differences in sleep quality among college students of different genders too. Compared with females, males had worse sleep efficiency (SE), shorter total sleep time (TST), and more awaking times (AT). In addition, 3 days was the minimum effective length for SAMI to shorten objective SOL, and 2 days was the minimum effective length to shorten the subjective SOL of college students. The findings of this study suggest that SAMI can improve subjective sleep quality, shorten objective SOL, and reduce anxiety and depression in college students. Interventions for more than 3 days had a significant effect on shortening SOL and long-term effects seemed to emerge after 3 weeks.

REM Sleep Impairment May Underlie Sleep-Driven Modulations of Tinnitus in Sleep Intermittent Tinnitus Subjects: A Controlled Study

(1) Background: Poor sleep and fragmented sleep are associated with several chronic conditions. Tinnitus is an auditory symptom that often negatively combines with poor sleep and has been associated with sleep impairment and sleep apnea. The relationship between tinnitus psychoacoustic characteristics and sleep is still poorly explored, notably for a particular subgroup of patients, for whom the perceived loudness of their tinnitus is highly modulated by sleep. (2) Methods: For this observational prospective study, 30 subjects with tinnitus were recruited, including 15 "sleep intermittent tinnitus" subjects, who had reported significant modulations of tinnitus loudness related to night sleep and naps, and a control group of 15 subjects displaying constant non-sleep-modulated tinnitus. The control group had matching age, gender, self-reported hearing loss grade and tinnitus impact on quality of life with the study group. All patients underwent a polysomnography (PSG) assessment for one complete night and then were asked to fill in a case report form, as well as a report of tinnitus loudness before and after the PSG. (3) Results: "Sleep Intermittent tinnitus" subjects had less Stage 3 sleep (p < 0.01), less Rapid-Eye Movement (REM) Sleep (p < 0.05) and more Stage 2 sleep (p < 0.05) in proportion and duration than subjects from the control group. In addition, in the "sleep Intermittent tinnitus" sample, a correlation was found between REM sleep duration and tinnitus overnight modulation (p < 0.05), as well as tinnitus impact on quality of life (p < 0.05). These correlations were not present in the control group. (4) Conclusions: This study suggests that among the tinnitus population, patients displaying sleep-modulated tinnitus have deteriorated sleep quality. Furthermore, REM sleep characteristics may play a role in overnight tinnitus modulation. Potential pathophysiological explanations accounting for this observation are hypothesized and discussed.

External Auditory Stimulation as a Non-Pharmacological Sleep Aid

The increased demand for well-being has fueled interest in sleep. Research in technology for monitoring sleep ranges from sleep efficiency and sleep stage analysis to sleep disorder detection, centering on wearable devices such as fitness bands, and some techniques have been commercialized and are available to consumers. Recently, as interest in digital therapeutics has increased, the field of sleep engineering demands a technology that helps people obtain quality sleep that goes beyond the level of monitoring. In particular, interest in sleep aids for people with or without insomnia but who cannot fall asleep easily at night is increasing. In this review, we discuss experiments that have tested the sleep-inducing effects of various auditory stimuli currently used for sleep-inducing purposes. The auditory stimulations were divided into (1) colored noises such as white noise and pink noise, (2) autonomous sensory meridian response sounds such as natural sounds such as rain and firewood burning, sounds of whispers, or rubbing various objects with a brush, and (3) classical music or a preferred type of music. For now, the current clinical method of receiving drugs or cognitive behavioral therapy to induce sleep is expected to dominate. However, it is anticipated that devices or applications with proven ability to induce sleep clinically will begin to appear outside the hospital environment in everyday life.

Systematic review: auditory stimulation and sleep

STUDY OBJECTIVES

Auditory stimulation devices (white and pink noise) are used to mask sounds and facilitate relaxation and sleep; however, the effectiveness of this intervention is not well established. This systematic review examined the scientific literature for the effect of specific types of auditory stimulation on sleep outcomes in adults.

METHODS

The PRISMA Statement guided this review. Searches were conducted in nine databases for intervention studies that could easily be employed in clinical practice. We excluded other types of auditory stimulation (music alone, binaural tones, and synchronization). Two reviewers screened abstracts and full-text articles for eligibility, with conflicts resolved by a third reviewer, and extracted data. Risk of bias was assessed with the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies.

RESULTS

34 studies reported results of 1,103 persons participating in three categories of interventions: white noise (18), pink noise (11), and six multi-audio (some combination of white, pink, music, or silence). Nineteen studies had positive findings in terms of improving sleep outcomes: 6 white noise (33%), 9 pink noise (81.9%), and 4 multi-audio (66.7%). Multi-audio had the lowest (better) risk of bias (mean/SD: 1.67/0.82) compared to white (2.38/0.69) and pink noise (2.36/0.81).

CONCLUSIONS

Although there was no strong evidence to support use of auditory stimulation, none of the studies reported any adverse effects with short-term application of auditory stimulation during sleep. Future research needs to include confounding factors that can affect outcomes, including one's noise sensitivity, personality, and other conditions or medications that may affect sleep.

Variable and consistent traffic noise negatively affect the sleep behavior of a free-living songbird

Anthropogenic noise is a ubiquitous disturbance factor, which, owing to the extensive nature of transportation networks, and ability of sound waves to penetrate distances, has wide-reaching impacts on biological communities. Research effort on biological effects of anthropogenic noise is extensive, but has focused on waking behavior, and to our knowledge, no published experimental study exists on how noise affects sleep in free-living animals. Sleep plays vital functions in processes such as cellular repair and memory consolidation. Thus, understanding the potential for noise to disrupt sleep is a critical research objective. Whether different noise regimes exert distinct effects on behavior also remains poorly understood, as does intraspecific variation in noise sensitivity. To address these knowledge gaps, we used a repeated-measures field experiment involving broad-casting traffic noise recordings at great tit (Parus major) nest boxes over a series of consecutive nights. We evaluated whether increasing the temporal variability and amplitude of traffic noise increased deleterious effects on sleep behavior in free-living great tits, and whether individuals differed in the magnitude of responses. We found that traffic noise reduced sleep duration, proportion, and bout length, and induced birds to exit nest boxes earlier in the morning. There was some support for a stronger effect of more variable noise, and relative to lower amplitude noise, higher amplitude noise resulted in less and more fragmented sleep. Effects of noise on sleep duration were stronger in older adults, and substantial, repeatable variation existed in individual responses. We demonstrate for the first time that anthropogenic noise can have strong effects on sleep in free-living animals, which may have cascading effects on waking behavior, physiology and fitness. Results suggest that reducing the amplitude of traffic noise may be an effective mitigation strategy, and that differences in individual sensitivity are important to consider when evaluating effects of noise exposure. CAPSULE: Experimental exposure to temporally variable and consistent traffic noise negatively affected sleep behavior in a free-living songbird.

Evidenced-Based Review and Evaluation of Clinical Significance: Nonpharmacological and Pharmacological Treatment of Insomnia in the Elderly

Insomnia in the elderly is a prevalent condition that poses treatment challenges to practitioners across medical fields. There are many behavioral and other nonpharmacological therapies, 18 Food and Drug Administration-approved pharmacotherapies, and numerous off-label, over the counter and alternative treatments. Most reviews on this subject focus either on pharmacological treatments or behavioral treatments. The authors provide a combined review of available pharmacological and nonpharmacological treatments. The authors narratively reviewed each treatment from our literature search, tabled results with the highest level of available evidence on 5 major sleep outcomes and evaluated these results for clinical significance. The authors also evaluated the safety of pharmacotherapies within the context of the 2019 Beers Criteria for Potentially Inappropriate Medications in the Elderly. The authors found the most rigorous evidence supporting Cognitive Behavioral Therapy for Insomnia as a first-line treatment option, with longer lasting therapeutic effects than treatment with pharmacologic agents alone. The authors also found evidence of similar outcomes from other behavioral interventions, such as Brief Behavioral Therapy for Insomnia and relaxation training. The authors found 4 studies, 2 on relaxation training, 1 on sleep restriction, and 1 on stimulus control limited to the elderly with clinically significant results. The authors found no pharmacological studies limited to the elderly on treatments not contraindicated by Beers criteria with clinically significant results. The authors discussed the challenges of determining clinical significance in sleep studies, the lack of studies restricted to the elderly, and the role of placebo effect.

The effects of white noise on sleep and duration in individuals living in a high noise environment in New York City

INTRODUCTION

Undisturbed sleep has been shown to be important for both health and quality of life (Medic et al. [7]). The World Health Organization estimates that nearly 25% of the population suffers from disturbed sleep due to environmental noise (Health TWECfEa, [2]). Sleep disturbance associated with elevated noise levels is particularly prevalent in metropolitan areas. Our study tested the hypothesis that white noise would improve sleep in New Yorkers complaining of sleep difficulty due to elevated sound levels.

METHODS

Ten adult participants were included in this study. All participants were recruited from a New York City based sleep clinic. Inclusion criteria was based on the presence of sleep disturbance and the reporting of high levels of environmental noise in participants' sleep location. The study was conducted using a within-subject, ABA design, with baseline, treatment phase, followed by another baseline (washout) period. Each phase lasted one-week, during which noise level and sleep were assessed. The treatment consisted of the application of a white noise device (Dohm Classic by Marpac, LLC) in the participants' bedroom. Sleep parameters were measured subjectively using the Consensus Sleep Diary (Carney et al. [15]), and objectively using a Motionlogger Actigraph.

RESULTS

Paired sample t-tests were conducted to evaluate the hypothesis that white noise improves sleep in a high noise environment. Significance was found on the variables WASO, as measured by actigraphy, t(9) = 3.438, p = 0.007 and sleep latency as measured by sleep diary, t(9) = 2.947, p = 0.016. There was a trend toward significance on the number of awakenings during the night, as measured by sleep diary, t(9) = 2.622, p = 0.028 (Holm's sequential correction of p-value required a value of <0.01 to find significance on this comparison) and sleep efficiency (actigraph), t(9) = -2.121, p = 0.063.

CONCLUSION

Our data show that white noise significantly improved sleep based on subjective and objective measurements in subjects complaining of difficulty sleeping due to high levels of environmental noise. This suggests that the application of white noise may be an effective tool in helping to improve sleep in those settings.

Noise as a sleep aid: A systematic review

White noise is purported to mask disruptive noises in the bedroom environment and be a non-pharmacological approach for promoting sleep and improving sleep quality. We conducted a systematic review of all studies examining the relationships between continuous white noise or similar broadband noise and sleep (PROSPERO 2020: CRD42020148736). Animal studies and studies using intermittent white noise to disrupt sleep or enhance slow wave activity were excluded. Two reviewers independently screened titles and abstracts of articles from three databases and assessed risk of bias for the 38 included articles. The primary outcomes described sleep onset latency, sleep fragmentation, sleep quality, and sleep and wake duration. There was heterogeneity in noise characteristics, sleep measurement methodology, adherence to the intervention, control group conditions or interventions, and presence of simultaneous experimental interventions. There was perhaps resultantly variability in research findings, with the extremes being that continuous noise improves or disrupts sleep. Following the GRADE criteria, the quality of evidence for continuous noise improving sleep was very low, which contradicts its widespread use. Additional research with objective sleep measures and detailed descriptions of noise exposure is needed before promoting continuous noise as a sleep aid, especially since it may also negatively affect sleep and hearing.

Recent Progress in Sleep Quality Monitoring and Non-drug Sleep Improvement

Insomnia is one of the most common health risk factors in the population as well as in clinical practice, which is associated with genes, neuron, environment, behavior, and physiology, etc. This review summarizes the recent progress in sleep quality monitoring and non-drug sleep improvement. The innovation of wearable and effective invention suggests a new approach and have deep implications toward sleep improvement and yet, the health care innovation system is also facing the challenge to foster the progress.

Acoustic white noise ameliorates reduced regional brain expression of CaMKII and ΔFosB in the spontaneously hypertensive rat model of ADHD

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ΔFosB was reduced in the DL-PFC, DLS and nAc in SH rats.

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Acoustic noise normalized ΔFosB expression in the DL-PFC and nAc of SH rats.

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CaMKII expression was reduced in the TMN in SH rats.

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Acoustic noise increased CaMKII expression in the TMN in both strains.

Loud (≥70dBA) acoustic white noise improves cognitive performance in children with ADHD as well as skilled reach and rotarod performance in the spontaneously hypertensive (SH) rat model of ADHD. To investigate how acoustic noise influences the brain activity in the SH rat model of ADHD, immunohistochemical staining of two neuronal activity and plasticity markers, Ca²⁺/Calmodulin dependent protein kinase II (CaMKII) and ΔFosB, was evaluated in Wistar (n = 24) and SH (n = 16) rats after repeated exposure to acoustic noise or ambient silence. Other SH rats (n = 6) were treated with repeated methylphenidate (MPH). Expression of CaMKII was reduced in the tuberomammillary nucleus (TMN) of the SH rat compared to Wistar but not in the nucleus accumbens (nAc) or the dorsolateral prefrontal cortex (DL-PFC). In the TMN, the expression of CaMKII was increased by noise in both strains. ΔFosB expression was reduced in nAc, DL-PFC and the dorsolateral striatum (DLS) of the SH rat compared to Wistar. Exposure to acoustic white noise significantly increased ΔFosB expression in the nAc and DL-PFC but not in the DLS of SH rats. The results indicate that acoustic noise shifts a reduced neuronal activity in the nAc, TMN and DL-PFC in SH rats toward the normal levels of activity in outbred rats. This may explain why noise has benefit selectively in ADHD.

The effect of air conditioner sound on sleep latency, duration, and efficiency in young adults

BACKGROUND

Many individuals complain of disturbed sleep during the wintertime when their air conditioner (AC) is off. Therefore, we conducted this study to objectively assess the impact of AC sound on sleep latency, sleep duration, and sleep efficiency.

METHODS

An experimental study was conducted on 48 healthy young adults, in their homes, to assess the effect of a standardized AC white noise, on sleep latency, duration, and efficiency, while simultaneously monitoring light intensity and room temperature. The study was conducted during the winter months. Sleep quality was objectively assessed using sleep actigraphy. Participants were monitored for two nights, during which two different, randomized sets of conditions were used: During one of the nights, the adults were exposed to 43 dB AC white noise; during the other night, adults were not exposed to the AC white noise.

RESULTS

Actigraphy results showed that the mean sleep duration during the AC sound nights (ASNs) was 466.8 ± 60.8 min, compared to 478.8 ± 55.4 min during the non-AC sound nights (NASNs) (P = 0.6). Sleep-onset latency was 10.8 ± 15.2 min and 15.1 ± 18.2 min during the ASNs and the NASNs, respectively (P = 0.8). Moreover, there was no difference in sleep efficiency, 81% ± 7.8% vs. 78.8% ± 15.4% in the ASNs and NASNs, respectively (P = 0.9).

CONCLUSION

AC sound had no significant positive effect on sleep duration, latency, and efficiency.