Skipped all the nap last night and went to bed at 3:00 a.m. Beer defenitely does affect your sleep because I am sleepy all day today and I had to take an extra nap. It is interesting how I am accustomed to take a short nap when I feel tired.

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3:00 a.m. -- 9:00 a.m. Long core sleep.
10:00 a.m. -- 10:30 a.m. Nap
5:00 p.m. -- 5:30 p.m. Nap

I became very sleepy at around 2 a.m. last night and ended up going to the bed. I did take a nap at 1 a.m. and it didn't really help. I think the only way to go pure polyphasic is through vocation. Having deadline and a whole bunch of work to just make it very risky.

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2:30 a.m. -- 7:30 a.m. Core sleep
1:30 p.m. -- 1:50 p.m. Nap
6:00 p.m. -- 6:30 p.m. Nap

I am thinking of going pure polyphasic this weekend. Other than that, really nothing too much to log here. I'll see how tired I am tonight then I'll decide.

(9:58 p.m.) Took a nap but couldn't very well sleep, even though I did feel tired. I'll try another nap at 1 a.m. and see if I can go pure polyphasic.

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2:30 a.m. -- 7:30 a.m. Core sleep
9:00 a.m. -- 9:30 a.m. Napped well
1:20 p.m. -- 1:50 p.m. I thought I couldnot sleep at the beginning but I did in the end.
5:10 p.m. -- 5:40 p.m. Napped
9:10 p.m. -- 9:50 p.m. Napped a little bit, well, it is better than nothing.

4 and half hour sleep last night. The reason of that was because I napped at 7:30 p.m. instead of 5 p.m. and skipped the rest of the nap yesterday. Believe it or not, this turns out to be better than I expected. Just like I noticed before, a 4 and half hour core sleep is the minimum that one can do without feeling too bad. The only way to achive shorter core sleep would be to go into polyphasic mode.

Here is another book I found on line while reading "Why We Nap". Biological Rhythms (Implications for the Worker) http://www.wws.princeton.edu/~ota/disk1/1991/9108_n.html

(1:55 p.m.) I think I'll just get when I wake up now. Yesterday I felt not bad after getting up from a 15 minutes nap. It does seem too short but I figure if I wake up by myself then probably I don't need any more naps. Also I noticed that these days I will wake up 15 minutes after I go to bed for the core sleep. I wonder if this is an indication that I am starting to adapt to the polyphasic schedule.

(11:59 p.m.) Skipped 9 p.m. nap and I am going to skip 1 a.m. nap also. In this way, I can go sleep at 1:30 a.m. and have a 4 hours and 30 minutes core sleep. My total sleep time would only increase by 30 minutes. I am still finishing the book "Why We Nap" and planning on going pure polyphasic.

Here is something I just read. In one of the researches, the "sleep-in-darkness index," (SIDI) is used. This is the percentage of the total sleep time (TST) occurring in the dark phase of an approximately 12:12 light-dark (LD) photoperiod. They analyzed 14 species of birds and 23 species of mammals. According to the chart, all the species either show SIDI of 40% - 70%, or 90%-100% (very few between 80% and 90%). So the conclusion is drawn that:

"Finally, there is possibly a kind of "forbidden zone" of sleep at night: no birds or mammals in this sample showed 70-80% sleep in darkness. This gap implies a divergent selection pressure such that either evenly polyphasic or almost strictly monophasic sleep patterns are favored, and it has implications for human sleep..."

I caculated my SIDI values. If I have 3 hours core sleep between 3 a.m. and 6 a.m. and nap every 4 hours starting at 9 a.m., then my SIDI will be 72.7%. If I have 4 hours and 30 minutes core sleep between 1:30 a.m. and 6:a.m., and take naps every 4 hours starting at 9 a.m. but skipping 9 p.m., then my SIDI will be 75%. If I don't skip 9 p.m. then it will be 76%. So it seems that my currently schedule is guaranteed to fail soonner or later. But this doesn't explain why 4 hours and 30 minutes core sleep is a lot easier than 3 hours pure sleep. Maybe the latter accumulate sleep debt a lot faster?

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2:30 a.m. -- 7:00 a.m. Stayed in bed until 7:30 a.m.
1:30 p.m. -- 1:46 p.m. Napped and woke up natually
4:50 p.m. -- 5:20 p.m. Napped and woke up in alarm

3 hours core sleep last night. Sleepy in the morning as usual. Due to a company meeting, I couldn't take the nap at 5 p.m. so I did one at 7:30 p.m. instead. My naps are kind of weird these days. I cannot sleep at the beginning then I will suddenly be awakened by the alarm clock, and still cannot figure out if I did fall asleep or not.

(12:29 a.m.) Borrowed "Why We Nap" (http://www.amazon.com/exec/obidos/ASIN/0817634622/104-0584692-0014348) from Nori and started reading it. Here is something very intersting (besides a lot of other stuff)

"Interestingly, the paradigm also revealed a "forbidden zone" for sleep in the early evening in which even sleep-deprived subjects show greater difficulty in falling asleep"

Well, I have been so frustrated by the fact that I couldn't nap at 9 p.m. And now I finally found something behind it! This is really exciting. Now I am feeling a lot better that I am considering staying up until 3 a.m. :D

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9:00 a.m. -- 9:30 a.m. Morning naps are good because I always feel sleepy in the morning. I mean really really sleepy.
1:20 p.m. -- 1:50 p.m. I think I slept in the end because I didn't hear the 'warning' alarms.
7:30 p.m. -- 8:00 p.m. The same as 1 p.m. nap. Woke up confused.

Did a reboot on the weekend. The reason for that was because I kept on slipping and I just couldn't hold on to it any more. After reboot, I felt great (duh...)

However, intersting thing happend that I must report here. I went to a friend's home for dinner on Sunday evening, which is last night. During the dinner, he mentioned that as part of his buddhism practice he meditates regularly. And the way he does is by slowing down his breathes and counting them. So at 9 p.m. last night, I decide to try a nap. Not feeling sleepy at all, I just start counting my breathes to pass the time. As he mentioned, he can spend 20 minutes on 200 counts, which is around 6 seconds per count. So I set 200 as my goal also, and the last count that I can now remember was somewhere in the 50's or 60's. I actually fell into deep sleep. When I was waken up by the alarm clock, I was totally disoriented and had no idea what time it was. I tried it again at my 1 a.m. nap also with success, although this time I think I reached a bit over hundred.

However, the bad news is that I didn't feel refreshed at all after 9 p.m. nap. Instead, I felt grumpy all the way till my 1 a.m. nap. I did feel a little bit better after sitting in the chair watching TV for 2 hours (which now I don' t think is a good idea).

(9:37 a.m.) Interesting, breathe counting technique, which is how now I decided to call it, really works. I was able to get in the nap, got out, then got in again. I kept waking up from the nap and continued counting somehow. I don't know why. Maybe that is part of the meditation. I regained conscious after 16 minutes and I decided to get up even though it was only half way through my 30 minutes nap. From the past experience, I always felt worse if I chose to wait for another 14 minutes for the alarm. I'll try it differently this time to see how it works.
(10:07 p.m.) So much for the "New" technique, I couldn't sleep, as usual. This is getting really frustrating. I am always feeling very tired at night and missing 9 p.m. nap always put things over the limit and I will slip some time down the road. I am really thinking of going pure polyphasic schedule just so that I can take a good 9 p.m. nap.

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3:00 a.m. -- 6:00 a.m. Core sleep
9:20 a.m. -- 9:37 a.m. Short nap. I thought I went to nap at 9:00 a.m. but the egg timer cannot lie. I guess I spent 20 minutes on reading.
1:10 p.m. -- 1:40 p.m. Napped
5:00 p.m. -- 5:30 p.m. Napped
9:30 p.m. -- 10:00 p.m. Cannot sleep no matter what. Felt very frustrated.