Slow wave entrainment using a smartwatch: a randomized crossover study

ISRCTN	ISRCTN17832710
DOI	https://doi.org/10.1186/ISRCTN17832710
Sponsor	Samsung Research America
Funder	Samsung Research America

Submission date: 19/01/2026
Registration date: 30/01/2026
Last edited: 30/01/2026

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Other

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Not provided at time of registration

Contact information

Prof Pattie Maes
Principal investigator

7 Massachusetts Avenue
Cambridge
02138
United States of America

Phone	+1 (0)617 359 0598
Email	pattie@mit.edu

Dr Nathan Whitmore
Scientific, Public

77 Massachusetts Avenue
Cambridge
02138
United States of America

Phone	+1 (0)5304002420
Email	nathanww@media.mit.edu

Study information

Primary study design	Interventional
Allocation	N/A: single arm study
Masking	Blinded (masking used)
Control	Placebo
Assignment	Crossover
Purpose	Device feasibility
Scientific title	Does slow wave entrainment with a smartwatch increase delta power and sleep quality in healthy adults compared to no intervention?
Study objectives	The goal of this study is to test whether rhythmic sound sand vibrations from a smartwatch can increase the amplitude of slow brain waves during sleep and assess the effects on sleep quality in healthy adults. Previous research using sleep lab systems has demonstrated that rhythmic stimuli can increase slow brain waves; this research will test whether we can achieve the same results using a smartwatch app.
Ethics approval(s)	Approved 16/10/2023, MIT Committee on the Use of Humans as Experimental Subjects (COUHES) (Room E25-143B, 77 Massachusetts Ave, Cambridge, 02139, United States of America; +1 (0)617 253 6787; couhes@mit.edu), ref: 2309001115
Health condition(s) or problem(s) studied	Sleep quality in healthy adults
Intervention	Active conditions: Slow wave entrainment using a smartwatch. Placebo condition: Participant wears smartwatch but no entrainment is performed. Crossover study where both participants receive placebo on one night and active stimulation on the other night.
Intervention type	Drug/Device
Phase	Not Applicable
Drug / device / biological / vaccine name(s)	Slow wave entrainment
Primary outcome measure(s)	Sleep delta power measured using home EEG at stimulation night of the experiment Awake cognition measured using computerized adaptation of Trail Making Task B at day after the stimulation night and the day after the placebo night Sleep disruption by stimulation measured using number of stimulation stops due to arousal at stimulation night of the experiment Sleep quality measured using Leeds Sleep Quality Evaluation Questionnaire at day after the stimulation night and the day after the placebo night Daily mood measured using Brunel Mood Scale at day after the stimulation night and the day after the placebo night
Key secondary outcome measure(s)	Percent of stimuli delivered in sleep stage N3 by the system measured using comparison of stimulation times to manual sleep stages from home EEG at stimulation night
Completion date	25/10/2024

Eligibility

Participant type(s)
Age group	Mixed
Lower age limit	18 Years
Upper age limit	120 Years
Sex	All
Target sample size at registration	90
Total final enrolment	93
Key inclusion criteria	Aged 18-120 years old
Key exclusion criteria	Age less than 18 or above 120 years
Date of first enrolment	08/04/2024
Date of final enrolment	23/10/2024

Locations

Countries of recruitment

United States of America

Study participating centres

Results and Publications

Individual participant data (IPD) Intention to share	Yes
IPD sharing plan summary	Stored in publicly available repository
IPD sharing plan	The datasets generated during and/or analysed during the current study will be stored in a publicly available repository (Open Science Framework, DOI not yet assigned) and on your project page at https://www.media.mit.edu/projects/sleep-entrainment/overview/ Non-identifiable data such as heart rate and motion data recorded by the watch and answers to questions about your sleep will be stored, used for future research studies, and may be shared with other researchers for future research studies without additional informed consent from you or your legally authorized representative. Your data might be shared with academic research institutions, non-profit entities, and/or for-profit entities. Your data may also be made publicly available in research data repositories such as the Open Science Framework and shared with our research sponsor (Samsung). Non-identifiable data will be stored indefinitely. Your data will be available for any research question, such as research aimed at understanding the development and causes of many diseases and conditions or the development of new scientific methods.

Editorial Notes

30/01/2026: Study's existence confirmed by the MIT Committee on the Use of Humans as Experimental Subjects (COUHES).