I tracked my sleep with an EEG-based setup at home from Dec 15 to Jan 15, which ended up covering a pretty realistic stretch of life: work stress, holiday travel, Christmas, New Year’s Eve, and then a return to routine with Dry January.

What made the month interesting was not that there were a few bad nights - that was expected - but which metrics moved, and how consistently they moved with specific disruptions. For context, I was looking at a nightly sleep score out of 40 \[built from total sleep time, sleep efficiency, deep sleep (N3), REM, fragmentation, wake after sleep onset (WASO), and sleep onset latency (SOL)\], alongside a separate 5-night trend score.

The overall pattern was fairly clean. During the work crunch from Dec 15-22, sleep was somewhat shorter and more fragmented. During holiday travel from Dec 23-26, the clearest changes were higher WASO and longer SOL. That reads very much like the classic first-night effect literature - sleep in a new environment is often less continuous even when total sleep time does not completely collapse. Around Christmas, REM dropped and fragmentation worsened, which is also very much in line with the literature on acute alcohol use and disrupted sleep architecture. Then New Year’s Eve was, unsurprisingly, the worst night of the month. Once I got back to a stable routine in January, the data normalized quickly.

The clearest single-night disruption was Dec 31: 4.2 hours total sleep, 8% REM, 65 minutes WASO, and a nightly score of 8/40. By contrast, the more stable stretch from Jan 6-15 sat mostly in the good range, with the trend score generally between 35 and 40 and sleep regularity staying above 95. 

A few things stood out:

1. Alcohol seemed to hit REM harder than deep sleep. The worst holiday nights were not just short-sleep nights; they were specifically nights where REM collapsed, especially around Dec 24-25 and Dec 31. That is broadly consistent with the literature, where alcohol tends to distort sleep architecture by disproportionately affecting REM and increasing later-night disruption.
2. Travel showed up more in WASO and SOL than in total sleep time. The travel block did not necessarily destroy duration, but it clearly made sleep more broken, with more wakefulness after sleep onset and longer sleep latency. Again, that is very much what the first-night effect literature would predict: unfamiliar sleep environments often show up more in continuity metrics than in raw hours slept.
3. Recovery was more about routine than about one heroic catch-up night. There was a 9.5-hour recovery night on Jan 1, but the more meaningful change came after the return to a stable schedule. From Jan 6 onward, the pattern became much less variable, and that was when the scores really stabilized.

So my main takeaway from the month was not "one bad night matters." That is obvious. The more useful conclusion was that different disruptions leave different signatures: alcohol mostly showed up in REM suppression, travel mostly in wakefulness and latency, and routine showed up in regularity and score stability. Anyways, I thought some of you might find this interesting.

I tracked a month of sleep with EEG through Christmas, travel, NYE, and Dry January - consistency mattered more than any single “perfect” night