Last night (December 19, 2012) I recorded my 1001st night of sleep data using the Zeo sleep monitoring system. I first started using the Zeo on August 6, 2009, and have worn it 81.25% of the time since (1001 out of 1232 nights). Most of the non-Zeo nights have been due to miscellaneous technical problems. I was surprised at how quickly I acclimated to wearing the headband while sleeping, and I have worn it consistently throughout this period, even on the non-Zeo nights. I’m confident that my data, even though it excludes roughly 1 out of every 5 nights, fairly represents my sleep experiences during this time.
The stability of my sleep patterns jumped out at me when I first reviewed the data. For more than three years the basic elements of my sleep–the amounts of REM, deep, and light sleep–have remained very consistent. A typical night includes approximately 30% REM, 15% deep, and 55% light sleep. These percentages vary to a degree, but I found the same fundamental proportions (something like 1/3 to 1/6 to 1/2) in nights of very short total sleep as well as nights of very long total sleep.
Using the Zeo’s aggregate sleep quality score, the ZQ, my monthly average has hovered around 90 for this entire period. My highest monthly ZQ was 96, in November 2010 (a year of a particularly restful Thanksgiving vacation) and my lowest monthly ZQ was 86, in June 2010 (of time of moving houses). My average ZQ was between 88 and 92 for 33 out of the 41 months for which I have data.
Over the next few weeks I’ll share more detailed analyses of this collection of data. During this time I have also been keeping a dream journal (@500 reports), and naturally I’ll be looking at patterns of dreaming in relation to the Zeo sleep measurements. Soon I should have all this material, Zeo + dream reports, available for anyone to study on the Sleep and Dream Database.
If you have any questions or hypotheses you think I should test with this data, let me know!