This lecture explores the evolution of sleep tracking, starting with Eugene Aserinsky's 1950s discovery of REM sleep and the development of polysomnography (PSG) as the gold standard for sleep analysis. We examine PSG's methodology, which measures various physiological signals to understand sleep architecture.
We then shift to modern consumer wearables like Fitbits and Apple Watches, discussing their technology, such as actigraphy and photoplethysmography, and comparing their capabilities to PSG. We highlight the strengths, limitations, and accuracy challenges of these devices in tracking sleep stages.
The lecture also covers ongoing research validating these wearables against PSG and addresses crucial privacy and data governance issues, emphasizing the importance of understanding how companies handle personal health data. This session provides a comprehensive overview of current sleep tracking technologies and their future prospects.
0:00 Polysomnography's origins
1:30 What is Polysomnography?
2:20 PSG Measurement: Combining many signals
4:10 Sleep 'scoring' and the hypnogram
5:10 Actigraphy for measuring sleep
6:00 Assessing sleep with wearables
6:38 Validating wearables against PSG
7:50 The challenges of conducting validation research with wearables
9:05 Concluding remarks