Enhancement of Sleep With Wearables

Study Overview
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Brief Summary
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Sleep, specifically deep sleep, plays a central role in healthy brain function, cardio-vascular processes, mood and quality of life. Auditory stimulation during one night of sleep has previously been shown to improve deep sleep and along with memory formation in both young and older adults. Yet, it remains unclear whether long-term auditory stimulation considerably improves sleep quality over longer time periods and how it affects daytime functioning such as cognition, mood, quality of life and peripheral functions (e.g. cardio-vascular). Due to the importance of deep sleep for brain and body and the presence of many conditions that involve reduced deep sleep (e.g. ageing) assessing the beneficial impact of long-term sleep enhancement and its consequences is of central interest.This study will assess the effect of auditory stimulation over two weeks (interleaved with a two weeks washout period) in a cohort of healthy young and older adults using portable recording and stimulation devices.

Official Title
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Enhancement of Sleep Slow Wave Activity Using Wearable Auditory Stimulation Devices and Its Consequences on Daytime Functioning: a Randomized, Counter-balanced Crossover Study

Conditions
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Sleep

Intervention / Treatment
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* Device: Application of tones
* Device: No application of tones


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Informed Consent as documented by signature For women: Hormonal contraception, if menstrual cycle is still present or has been present less than a year ago Good general health status Stable home situation (e.g. long-term place to live) that allows for reliable application of intervention for the duration of the study Male and Female subjects 18-35 years of age or 60-84 years of age German speaking Exclusion Criteria: Women who are pregnant or breast feeding, Known or suspected non-compliance, drug or alcohol abuse, Intake of sleep altering medication Inability to follow the procedures of the study, e.g. due to language problems, cognitive deficits Participation in another study with investigational drug within the 30 days preceding and during the present study, Presence or history of diagnosed psychiatric/neurologic disorder/lesion of the central nervous system (CNS), Diagnosed internal disease, Presence of sleep disorders, Shift-work (work during the night) or situations that require several awakenings during the night (e.g. newborn) Travelling more than 2 time zones in the last month before intervention starts or during intervention (study start will be shifted accordingly) Hearing disability/ hearing aid Skin disorders/problems in face region that will worsen with /not allow adhesive electrode application Nicotine/Cannabis use High caffeine consumption (> 5 servings/day; including coffee, energy drink)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 84 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Application of tones<br>During non-rapid eye movement (NREM) sleep short tones will be played | Device: Application of tones<br>* During NREM sleep, tones (max. 60 dB) will be played using a portable, safe, in-home device. This device records biosignals (e.g. brain activity) and precisely times the tones during NREM sleep. It was developed and produced by the ETH Zurich and approved for use in this study by Swissmedic<br>|
| Sham Comparator: No application of tones<br>During NREM sleep no short tones will be played | Device: No application of tones<br>* This is the sham-control intervention; The device will only record biosignals but will not play tones.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sleep quality | Objective information about sleep macro- and microstructure will be assessed including measures like sleep architecture, amount of slow wave activity (SWA), amount of spindles, awakenings during sleep, and sleep fragmentation. In addition, subjective sleep quality will be obtained by questionnaires every morning over the intervention period. These measures will show whether auditory stimulation enhanced overall sleep quality compared to sham. | From baseline period to study completion, assessed up to 2 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Daily functioning - Mood | Mood will be digitally assessed using a daily mood scale over the intervention period | From the beginning of the first intervention period until the end of the second intervention period, assessed within a time period up to 6 weeks | 
| Daily functioning - Quality of life | Quality of life will be assessed using a World Health Organization (WHO) quality of life assessment before and after each intervention period | From the beginning of the first intervention period until the end of the second intervention period, assessed within a time period up to 6 weeks | 
| Daily functioning - Vigilance | Vigilance will be assessed using a digital psychomotor vigilance task, assessed daily over the intervention period | From the beginning of the first intervention period until the end of the second intervention period, assessed within a time period up to 6 weeks | 
| Daily functioning - Cognition | Cognition will be assessed using a digital test battery before and after each intervention | From the beginning of the first intervention period until the end of the second intervention period, assessed within a time period up to 6 weeks | 
| Physiological parameters - Cardiovascular | R-R interval based assessments will be obtained using wearable monitors | From baseline period to study completion, assessed up to 2 months | 
| Physiological parameters - Physical activity | Physical activity levels will be obtained using wearable monitors | Through study completion, approximately 2 months |