Z4: Second 'short night'

Having had one short night and then -to be honest- survived the day after, I wondered how difficult it would be to repeat the feat. Would it be much harder to do two nights in a row, or would I start adapting already?

Not surprisingly, by midnight I was already tired, but from previous experience I do become more wakeful at those hours. I also had a later-than-usual cup of coffee at 20:00.

This time, I thought I'd try to actually be productive and do something work-related. To get into the groove, I started by writing two more entries for this blog. Once I was done with that, I spent over an hour reading up on a specific research topic that I would need on Friday morning for a meeting. Read introductory material from emails, then some summaries from OMIM and PubMed, skimmed a relevant paper. With some background info, I went ahead and studied the relevant genomic locus at the UCSC browser and in Gestalt (my genome analysis software), searched online databases for additional relevant information. Being much better informed, I sent a quick email answering a question from a collaborator... at 2:10 am.

At that point I was very pleased with having had the opportunity to study the topic ahead of the morning meeting. I was also much more tired, presumably at least in part due to having done a more intellectual effort. So I called it a night, and after winding down, I went to sleep at 2:35 am, earlier than intended. I reckoned there might be the extra benefit of going to sleep right after having studied the topic at hand.

So I wore the Zeo again and, since I was turning in 25 minutes earlier than intended, I decided to try the feature of the Zeo that is supposed to wake me up at the optimal point before the set alarm time. According to the Zeo, I again fell asleep in 8 minutes. I had various dreams, and was woken up by the Zeo's alarm. I turned it off, and before I could anything else... my regular alarm went off as well, meaning the Zeo woke me up at 6:30, not at the optimal time before it.

This time I was less surprised to see that it had failed again, though not less disappointed. Again, it had stopped recording after exactly one hour, and the recording indicated largely only light sleep.

As I was preparing the coffee around 8:30 in the office, the Sun was shining, so I spent a couple of minutes facing the sunshine. Very invigorating, of course. The day passed in meeting after meeting... but my wakefulness was much improved as compared to the previous day. Whether that was due to the sunlight boost or to incipient adaptation, I can't tell.

Z3: First 'short night' experiment

The first full night with the Zeo confirmed the expected typical sleeping pattern: during the first half of the night, there is little more than light sleep and waking periods. I decided then to do an experiment, and see what would happen if I'd skip that first half of the night. That meant going to sleep around 3 am. This sounded a bit daunting at first, but then again I not infrequently go to bed after 1 am.

The evening of March 21st I felt wakeful (and not tired) enough to go ahead with this plan. I simply went through the usual evening routine, except when it was time to go to sleep... I just carried on. Since the point was to test the ability to stay awake, I opted not to engage in anything too intellectually demanding. It ended up being a rather useful time: I started this blog, wrote the first three entries (with very minimal editing - it's almost 'flow of mind' writing), watched a TED talk, did a set of 15 push-ups, watched some stuff on Netflix, listened to music off youtube while reading and catching up on several backlogged RSS feeds.

Towards 3 am I wrapped the extended day up, put the Zeo on and went to sleep. I was hoping to observe: 1) a very short time to fall asleep, 2) relatively little light sleep, 3) a much higher proportion of REM.

Three and a half hours later, the alarm clock sounded. I woke up, noticed the headband was still on, recalled the plan, and with great interest and curiosity turned to the Zeo bedside console to look at the graph, and saw (a black and white version of) the following:

Even though I wasn't feeling dazed at all, it took me a little while to figure it out. Apparently, the Zeo recorded just the first hour of sleep, most of which was again light sleep, and then... it quit, for no obvious reason. I didn't take the headband off, it was on when I woke up. The three marks on my forehead were there. So why did it stop recording after exactly one hour? No idea.

The first expectation checked out fine: it apparently took me just 5 minutes to fall asleep. The second expectation didn't pan out for the time of recording (just 2 minutes in REM, 1 minute in deep sleep). As for the third, I have no idea, beyond the fact that I remembered plenty of quite vivid dream activity. Who knows, perhaps a big fraction of the remaining 2.5 hours of sleep were spent in REM, but the Zeo failed to record it, and I'm left in the dark.

So after sleeping half a night, what was my day like? In short, and not surprisingly, it was low energy and sleepy. On the other hand, it was not extraordinarily so - it was within the range of what I experience with "a full night" (except again, not infrequently my nights are short). The day seemed to pass rather quickly and wasn't very productive (which can also be explained by the meetings).

Of course, for it to be a reasonable sleep pattern I had to plan for one or more siestas (which I never do). I did the calculation for the simplest possible pattern: biphasic, with a siesta diametrically opposite the 'core' night sleep. That would be, for example, 16:30-17:00 for a half hour siesta.

I had coffee as usual around 8:30. I went for a quick rest from 11:10-11:30, but didn't sleep. Second coffee at 13:30 after lunch. Towards the end of the workday I felt tired enough, and the planned siesta sounded like a good prospect. I dozed off between 16:30-17:00 as intended. Took a while to fall asleep, but it happened, and when the alarm sounded, I felt much refreshed. The commute back home (walk+bus) helped wake me up further. Around 20:00 I had a third cup of coffee, and also did six sets of 15 push-ups without any hardship. At that point, it looked like the first day of this experiment had been successful enough (except for the technological failure), and I was up for trying a second day.

Z2: Some missing data

The second night with the Zeo was somewhat different from the first one. First of all, I learned my lesson, and this time the headband straps were fully extended. Significantly less pressure on the forehead meant it was less annoying, and presumably would leave less obvious marks.
I also went to bed much earlier - barely after midnight. I was fully awake, and essentially went to bed out of routine, and "to get a good night's sleep" of 6.5 hours. (And don't tell me I need to sleep 8 hours!)

This time there was a lot of tossing around until I managed to fall asleep. As you can see from the graph, I woke up several times during the night (the Zeo reports 7 times), and most of the time was spent in light sleep:

In numbers: total sleep time of 4:45 hours, 16 minutes to fall asleep, 51 minutes in REM, 21 minutes in deep sleep. There are also three unexplained gaps in the data, during which no signal was captured, for unspecified reasons.

The Zeo computes a "sleep score" that largely rewards REM and deep sleep, and takes points for wake time. The first, short night reached a score of 36, which is very low - around half as much as they think I should be getting. This night, despite the longer time spent in bed (and without tossing the sensor aside...), the score reached a mere 43. This seems to confirm that, indeed, my sleep is a bit of a mess, and rather inefficient.

I woke up to the sound of the regular alarm clock, feeling ok - pretty typical. The energy level during the day was also quite typical. Interestingly enough I remember the alarm waking me up during a dream, but not a particularly vivid one. If the graph is to be trusted, I was in light sleep, a few minutes after REM, so perhaps I wasn't actually dreaming when the alarm went off - I only vaguely remembered the last dream. Details about the dream then vanished quickly.

Z1: First night with the Zeo

March 19th-20th was the first night I used the Zeo sleep tracker. I went to sleep rather late (which is not that unusual...), around 1:30 am. I opened the headband straps to their maximum (big head apparently), put the headband on, and tightened it a bit (thinking it would fall off otherwise). I looked at the display on the bedside console for a bit, and sure enough, a few moments later an icon changed to indicate the headband was getting (and transmitting) brain activity signals. So I went to sleep.

It didn't take long to figure out that no, wearing a headband to sleep is not comfortable. I kind of forced myself to ignore it, thinking that once I fell asleep, it wouldn't matter.

The expectation was, of course, that I'd wake up in the morning, take the headband off, and immediately get a very interesting graph showing me how I slept.

The situation was slightly different, and actually rather hilarious. I woke up around 6:15, and immediately noticed I wasn't wearing the headband. Moreover, the graph ended abruptly around 5:15. The first thought was, of course - it fell off! But then I remembered: I actually dreamt that it was time to wake up, and thus... removed the headband, in my sleep, and tossed it to the side of the bed. This very vivid dream apparently happened around 5:15. When I then eventually woke up at 6:15, I momentarily panicked thinking I had overslept...

Here is the graph:

In numbers, the Zeo reported for that night: total sleep time of 3:30 hours, 8 minutes to fall asleep (definitely not matching my perception, and actually not matching the displayed 15 minutes of wake time...), 22 minutes in REM sleep, 21 minutes in deep sleep.
But of course, most of the last hour before waking was chock-full of vivid dreams, i.e. lots of REM sleep. This wasn't captured at all, leading to the appearance of a very short and inefficient night. In reality, I woke up very energized, and this lasted most of the day. I couldn't find any way to "correct" the result (that is, indicate the fact that I actually slept longer). I kind of expected the mysleep.myzeo.com online tool to support this.

Soon after getting up I noticed a small detail: my forehead had three rather unsightly marks, where the headband sensors pressed. Over an hour had passed since I had removed it, and yet they were quite visible. It took some 3-4 hours for them to vanish. Clearly, I had over-adjusted the headband straps...

Quantified Self, and the Zeo

I have been also interested in the Quantified Self "movement" (if that is the right word to use for this). Capturing information has always seemed like the obvious thing to do, and once the information is captured, the natural thing to do is to visualize it in some way - at least for a visual thinker like me!

For a few years now, I've been tracking my weight. Not daily - I weigh myself every couple of weeks. What I do daily is to track the number of steps, using a simple pedometer. I've tracked this since March 2010, and the resulting graph is rather interesting. (I'll post about that at some point.)

Thinking of sleep, what can be quantified? Some things are obvious but not trivial to define, like the level of wakefulness along the day. Some are much easier to define and quantify, like how long one slept during the night, how much time was spent in the various sleep phases, etc. Of course this requires special equipment, but the technology for capturing this information is becoming very accessible.

I have been paying some attention to the sleep tracking options for a couple of years. In particular, the Fitbit and the Zeo looked like the most relevant options. In several senses, the Fitbit looked like the best option, but my understanding is that its sleep tracking is entirely dependent on capturing movement. The Zeo on the other hand is supposed to detect brain activity patterns, which seems like the best way to quantify this type of information.

Last week I reviewed again details about the Zeo, read plenty of descriptions of personal experiences using it, and in truth I was surprised to find that it was much cheaper than I remembered it. I ended up deciding to give it a try, so I ordered it through Amazon, and it arrived on Monday, March 19th, 2012.

Since I don't own a mobile, I purchased the "bedside" version of the Zeo. Setting it up was trivial. Most of the buttons and menus were completely intuitive. Monday night, the Zeo headband was charged and ready for test driving.

Some background

Polyphasic sleep has intrigued me for a long time, but my knowledge of it was superficial at best. This changed recently, among others due to mention in LifeHacker. One tidbit that struck me was the idea that what we consider now "standard", namely sleeping one continuous block of time during the night, is actually a modern practice. Before electric lighting allowed us to stay active into the night, people apparently slept in what is essentially a biphasic mode, going to sleep soon after dark, waking up around midnight, then falling asleep again for a "second sleep". The time between sleeps was variously devoted to meditation, prayer, socializing, and obviously sex.

If monophasic sleeping is something evolutionarily and technologically new, what are the implications? We are all very aware of the difficulty many people have getting up in the morning, or falling asleep at night, or even the physical pain that can arise from spending so many hours in bed (this is probably very age-dependent).

In any case, one thing many if not most people seem to agree on is that we would like to have more hours in the day. I personally cannot understand "boredom". There are so many interesting things to do! In an era of readily available information, it is all too easy to accumulate huge backlogs of things one wants to read, talks/movies one wants to watch, music one wants to sample. There is also plenty of content one may want to produce (read: paper writing!) but there aren't enough hours in the day, and it's all too easy to be too tired to perform. So what is the solution?

During the last month I read quite a bit about different sleep patterns. I read about the 28 hour day, with sleep times shifting daily four hours at a time, coming back into sync with the standard 24-hour clock weekly. An interesting concept, but one that requires a very specific setup, and the gains appear to be rather limited. One ends up sleeping less, but not that much less.

Much more interesting are the "Uberman" and the "Dymaxion" sleep patterns: six evenly-spaced naps of 20 minutes each, or four naps of 30 minutes each, respectively... clocking a grand total of two hours of sleep per 24 hour period. Rather extraordinary if one can achieve it, and some of the reports online are extremely enticing. In particular, the resulting ability to fall asleep at will (and enter REM sleep directly) is very attractive. Conceptually, it is even more interesting that under either of these sleep patterns, one effectively doesn't have a time zone anymore. If one manages to sleep regularly every four or six hours (depending on the pattern), one lives in continuous time, barely punctuated by the short naps in a fully symmetric pattern. I do wonder how confusing this may be.

A less extreme regimen, and one that appears to be easier to achieve, is the "Everyman" sleep pattern. There are a few varieties of this, depending on how long the "core" night sleep is, and how many naps one takes along the day.

I have not yet decided what I'm going to attempt. My current guess is that some variant of Everyman may be best suited for my needs and possibilities.

By way of introduction

Here I am, considering an experiment in polyphasic sleep. Well aware that there will be lots of interesting detail to capture, particularly during the transition.. and that memory will probably fail due to sleep deprivation, again particularly during the transition.


In other words, it would be a good idea to post ideas, findings, experiences from the start, and not start accumulating material in my mind... only to be forgotten.


It sounds like a great excuse to finally get into blogging. So here it is. All details subject to change.


Hello, world.