Today felt much the same as yesterday. Generally I was in a good mood and felt rested. I was able to concentrate on tasks for long periods of time and had a very productive day.
My sleep pattern:
6am – wake up. This was the first core nap I have woken up from where I didn’t immediately spring out of bed. I felt almost comatose and thanks to the persistence of certain alarms I managed to make it out of bed without falling back asleep and oversleeping. I ate breakfast and went for a walk immediately. Upon returning home I felt rested and alert.
11am – First nap. I fell asleep quite quickly for this nap and slept for a solid fifteen minutes after which I woke up naturally.
11:20am – wake up. Upon waking up I felt fully refreshed and alert. This was a wonderful feeling, which compensated for the more difficult wake up from my core sleep.
4:20pm – Second nap. I didn’t fall asleep immediately. I cycled between feelings of falling asleep and being awake. I eventually fell asleep as I was my alarm had to wake me up.
4:40pm – wake up. No issues waking up. I didn’t immediately feel refreshed but after about twenty minutes I felt full functional.
9:40pm – Third nap. This was a disappointing nap. At about 8:40pm I began to feel tired. I feel like this is to be expected (albeit a little early today) as it means I am getting used to sleeping at this time. However, as soon as I lay down to sleep the world seemed to get incredibly loud. It took me ages to fall asleep (I’m not even sure if I did) and I do not feel very refreshed at this point (11:29pm).
10pm – wake up. I woke up just fine but it was a struggle to get out of bed. Like I said above, I don’t feel like I recovered at all during this nap.
Data:
Exciting news!! Thanks to David, I’ve started exploring the effects of polyphasic sleep on working memory. While I do not have a baseline to compare my results to I feel that any trend in (the hopeful) recovery of my lost sleep will still be apparent in the data. The specific test I have added is called an n-back task. It asks the user to recall the nth back object in a string of objects. I’ll try to explain: in a 2-back task the user sees a letter A. This is followed (after a few seconds) by a second letter, B. Then a third letter is added, say, C. If C is the same as A (the object that is two back from the current object) the user should provide some input (a mouseclick). If the user does not click when they should, or clicks when they shouldn’t, the program records an error. These errors are tabulated after 20 objects. This is repeated 3 times.
If it so happens that I score above 90% for a specific n-back test, the following day I will attempt an (n+1)-back test. Because I do not have a baseline for this test, I will not be able to actively tell how my performance scales with n, but I anticipate that this will be easy to determine once my experiment and recovery phase are complete.
The PVT went well today. I feel more able to concentrate then I was two days ago. Like I always seem to say, ‘I hope this actually shows up in the data’. I actually cheated a little bit today and glanced at a few of the data files from the past few days and….I can’t really say anything conclusive. I really wanted to do some analysis today but managed to restrain myself.
On the concentration front, I was able to read a number of pages from a review article I’m working through. I didn’t find it hard to concentrate and I could synthesize the new information with my current understanding of the subject.
There are two things I want to remark upon tonight. The first is my apparent lack of REM sleep. Don’t misread this last sentence. I’m not saying that I have been REM sleep deprived for the last 5 days. Instead, I am remarking upon the lack of vivid dreams throughout this experience. This doesn’t really worry me. I’ve never been a big dreamer (or at least I don’t remember my dreams). Through the last five days I have fallen asleep from a semi-meditative state. My mind was surprisingly calm and I didn’t face my usual restlessness when trying to sleep. I feel like my short naps have lasted for longer than 20 minutes, which could be a sign of REM sleep (as opposed to the vivid dreams). I just find it interesting that something so prolific on the polyphasic blogs has yet to rear its head in my experiment. Only more time will tell if this is actually the case, but its something for me to think about.
The second thing I want to talk about is the literature on sleep that pertains to polyphasic sleep. My literature search is far from fully comprehensive and focuses mainly on chronic sleep deprivation (what polyphasic sleep most resembles in my eyes) but should provide a bit of hard facts about the effects of messing with your sleep.
In Fatigue Models for Applied Research in Warfighting (Hursh, S.R., et al 2004) it is remarked that chronic sleep restriction is hard to model. But that’s not why I read this article. There is one graph on page 7 showing performance on various psychomotor vigilance tasks versus the number of days of sleep deprivation.
Basically, all I want you to see is that performance decreases linearly with the number of days of restricted sleep. When I perform my analysis I will compare my output to graphs such as these.
Another interesting article is Patterns of performance degradation and restoration during sleep restriction and subsequent recovery: a sleep dose-response study (Belenky, G., et al 2003). This study once again compares PVT performance across different amounts of time spent in bed, noting very similar findings as the other article I mentioned. The benefit of this study is that it also provides data on the amount of time spent in the different stages of sleep.
Have a read if you are interested. The study of sleep is quite convoluted and many articles will outright contradict each other. This all points towards more serious studies of sleep (if only ethics approval was a little easier).
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