Limitations of Sleep Tracking Apps and Hardware

Recently over at the Mac Power Users, someone asked whether it was worth trying to track sleep with Apple Watch apps. Another poster (“Rob”) asked whether consumer EEG devices (like Dreem) are any better. I provide some opinions (but no advice).

1. Actigraphy and ECG are not helpful in tracking sleep.
2. EEG is much better, so devices like Dreem are promising.
3. However, EEG, although widely used and super important scientifically, does have limitations.
4. Research linking even high quality EEG sleep tracking to quality of sleep shows remarkably little correlation. In other words, technical psychobiometric measures (EEG included) don’t correlate highly with answers to relevant questions like, “Did you have a refreshing night’s sleep?” Compare Dr. Jamie Zeitzer Associate Professor (Research) of Psychiatry and Behavioral Sciences (Sleep Medicine) at Stanford University presented a paper at the World Sleep Congress entitled “When a gold standard isn’t so golden:Predicting subjective sleep quality from sleep polysomnography” (PSG). He and others made this point.
5. Many insomnia theorists, based on polysomnography (EEG), used to claim (and some still do) that insomnia typically involves misperception of one’s sleep. Alison Harvey’s cognitive model of insomnia is an example. However, counter evidence recently arose based on fMRI research by Dr. Daniel Kay and Dr. Daniel Buysse. Moreover, Daniel Kay presented an analytical (a priori) argument against the concept of sleep-state misperception at the World Sleep Congress 2019.
6. obsession with sleep tracking is very risky. Insomnia researchers are nearly unanimous that monitoring sleep is a precipitating and perpetuating factor for insomnia. In that respect, Harvey’s model of insomnia is correct.

Implications

1. As noted elsewhere on this website, mySleepButton does not include much by way of sleep tracking or statistics. Having a general idea of how much sleep opportunity you have, and how much sleep you are getting is a good idea. Many people are more sleep-deprived than they realize. Psychologists have developed several traditional questionnaires to assess sleep that be used instead of tech. One can log one’s sleep using a plain text app and text expansion utility. (That’s what I do with 1writer app and TextExpander on iPhone, in a plain text version version of the mySelfQuantifier system concept, which I’ve adapted for iOS).
2. It is important for app developers and consumer EEG device manufacturers (like Dreem) to let people know about the foregoing issues that apply to their products.
3. EEG device manufacturers need to ensure that the analysis and interpretation of technical EEG data, even if processed through machine learning is not biased by the “old school” view of sleep state misperception. (AI is not without biases. Cf. the book by Gary Marcus Rebooting AI. See also the Manifesto for integrative design-oriented AI and cognitive science at CogZest.)
4. Some consumers would benefit from the assistance of a sleep expert to interpret their sleep data and/or receive advice about their sleep. Admittedly that is not practical or affordable for many, which is one reason why sleep tech is being marketed.
5. There’s a lot of high quality information about sleep available for consumers. However, some of it needs to be updated and “translated”. This post is an attempt to provide translation of recent information.
6. Caveat emptor applies. Consumers need to know the limitations of the tech they are using.

More about the World Sleep Congress 2019

Earlier, on this blog CogSci Apps mentioned that I presented three research posters with my academic colleagues at the 2019 World Sleep Congress . Check out this post for instance. The latter is an update to our theory of sleep onset and insomnolence.

More caveats

We do not provide professional advice on this site.

Hook productivity app

Incidentally, you can use the Hook productivity app to link related blog posts. For instance, I used Hook to link this blog post to the web page on Mac Power Users where I answered questions on this topic. I also linked this page to the plain text source file stored on my Mac. So I can instantly navigate between this web page and related information.

And you can do the same. With Hook, you can instantly navigate between related resources (be they websites, emails, files, or other types of information).