Schedule of Events | Symposia

Slow wave stimulation using a smartwatch improves sleep quality

Poster Session F - Tuesday, April 1, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom
Also presenting in Data Blitz Session 4 - Saturday, March 29, 2025, 10:30 am – 12:00 pm EDT, Constitution B.

Nathan W Whitmore¹ (nathanww@media.mit.edu), Wei Ting Samantha Chan¹, Abigail Dulski¹, Anita Podrug¹, Nelson Hidalgo¹, Nnamdi Obi¹, Varun K. Viswanath², Viswam Nathan², Pattie Maes¹; ¹MIT, ²Samsung Research America

Slow electrical waves in the cortex during sleep play a vital role in memory consolidation and restorative functions of sleep. Experiments that use rhythmic sounds to increase slow wave amplitude (closed-loop acoustic stimulation) have shown that increasing slow wave amplitude can improve measures of sleep quality and cognition. However, current systems used for slow wave enhancement are expensive, cumbersome, and fragile, limiting their use outside of research. To improve the usability of slow wave stimulation, we created a smartwatch app to stimulate slow waves using rhythmic vibration and sound. Stimuli are controlled using a machine learning model which uses motion and heart rate data to predict the optimal stimulus timing and intensity. We tested the effects of smartwatch stimulation in 106 participants who used the device at home. Stimulation (especially sound stimulation) increased frontal EEG delta power compared to no stimulation, replicating previous findings on the effects of slow wave stimulation. Continuous 0.8 Hz sound stimulation was more effective than vibration stimulation or intermittent stimulation. Participants with a large delta increase during stimulation showed improvements in self-rated sleep quality and mood and reduced errors on a trail-making task following stimulation. Our results suggest that smartwatch-based slow wave stimulation can replicate the effects of stimulation with more complex lab-based and EEG systems. Smartwatch stimulation could provide a path to wide use of slow wave stimulation for cognitive enhancement.

Topic Area: METHODS: Other