Some success to report following the last post so now the work "Failed" is removed from the title.
In the last post I reported a single sleep block ending in a refreshing dream state sleep. I also felt more active and inclined to get on and do things after this and so there was some success, although I was now waking up 12 hours later than I should be.
Now, knowing that the human body has a natural tendency to a 25 hour unregulated diurnal cycle and that shifting the clock back is harder than shifting it forward, the plan from then on has been aimed at moving the wake up time forward an hour or two per day, starting from 26 December.
The aim was to peg my wake up time and determine my target go-to-sleep time. Having woken up on Christmas Day at 1700 and reckoning on needing 7 or 8 hours sleep my aim was to go to bed at about 1000 on the first day, and then day by day push this forward an hour or two until I was going to bed at a more normal time. I reckoned this might be possible in about 10-12 days.
I have had some unexpected fortune on the first day because I could not get to sleep until 1400 and ended up sleeping for another 9 hours instead of 7 (which was an excellent start really because I leapt forward 8 hours on the plan instead of 2 hours). So I woke up at 2300 which meant that my wake up time just needed to be forwarded by another 8 hours.
The next day I slept another 10 hours but this was split across two periods, one starting much earlier than planned (asleep 1300 awake refreshed at 1900) and the other 0300 to 0700 . Now this is the time I should be waking up!!! So in 2 days I was already on target. Could it be sustained?
Across the last 48 hours I have again slept in two periods. A 2 hour period in the late afternoon (my twighlight doze) and a 7 or 8 hour period, the first of which left me waking up at 0700 again but the last leaving me awake at 0330. This happened because yesterday I responded to a feeling of sleepiness at 2000 and decided to go to bed instead of going out as planned. I am beginning to think that my problems begin when I ignore a sleep signal in the early evenings.
I also now think that 7 hours sleep is fine in summer but in winter I should be aiming for 9 hours per night, to some extent mirroring the lengthening nights of winter. I was curious to learn from Coturnix that 2 periods of sleep per night is a normal pre-electric light sleep pattern, with the first sleep happening at sundown. Maybe I should not worry that I am currently getting my 9 hours sleep over 2 periods.
And here is another interesting observation which I have not mentioned before but which is interesting to note. Last Christmas when I was living in England I went out for a brisk walk with my son who complained bitterly at how cold it was outside. I was wearing fewer layers of clothes than he yet did not feel the cold at all. Months later, on March 1st in fact, I woke up at 0700 and felt frozen to the bone. I immediately leapt into the shower, got dressed and then was amazingly active. I then realised that my depression had lifted but only later called into question whether that morning was any colder than any other morning. My central heating system was working so the thermostat should make the temperature inside the same as yesterday. A call to a friend confirmed that my coldness was purely experiential to me as the outside temperature had certainly not changed. Conclusion? Well I believe that in winter I become cold tolerant. I therefore think that mother nature prevents me from experiencing the cold in winter time and takes steps to ensure that I do not become accidentally cold exposed. So I am awake at night and I am encouraged not to go out in the day*. (*Another feature of my so called depression is that I never seem to want to venture out unless I am forced to... a behavioural trait that is certainly a winter-time one and led by instinct rather than logic).
The interesting thing this morning was that 0630, soon after getting up I suddenly felt terribly cold. Frozen to the bone in fact! Now again this was experiential because I was not cold at 0530 and the temperature inside is well regulated. Am I coming out of the depression? An hour later the feeling had gone.
I certainly hope so! But I must be careful here. In England my depressions normally come on bad in December and lift in early March. Here in Finland it came on bad in November. If controlled by the hours of daylight (which I am inclined to believe with the science community that it is) then I ought to expect it to run through to until March or even April. But I have been using my light box recently (and at some odd and un-recommended times but with the aim of aiding the shift in sleep times). I wonder if that has had an impact?
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The bimodal sleep pattern was first seen in laboratory animals (various birds, lizards and mammals) in the 1950s, 60s and 70s, i.e, before everyone moved their research to mice and rats who have erratic (un-consolidated) sleep patterns. The research on humans kept in constant conditions, as well as field work in primitive communities (including un-electrified rural places in what is otherwise first world) confirmed the bimodality of sleep in humans, particularly in winter.
During a normal night's sleep, REM occurs every 90 minutes or so. As the night progresses, the REM episodes get longer and the non-Rem periods in-between become shorter (thus still adding up to 90 minutes) as well as shallower. Thus, the really deep sleep (e.g, Stage 3) occurs only during first 1-2 cycles early in the night. Lack of Deep Sleep results in tiredness.
Usually adults wake up from REM (children do not), unless waking is forced (e.g., alarm clock). Research on relative roles of REM and NREM in consolidation of memory is very controversial (look for Jerome Siegel on Google Scholar). Growth Hormone surges during episodes of Deep Sleep, and falls during REM, and is almost undetectable during wakefulness.
In the morning, our body prepares us for waking by increasing blood levels of ACTH and cortisol (leading to preponderance of heart attacks at waking time). Our body temperature is the lowest just an hour or two before waking and highest an hour or two before falling asleep. If you felt a chill, it is because your clock is still at an pre-waking (late-night) phase.
Melatonin is secreted only at night (circadian clock time) and is not dependent on sleep. However, light tends to reduce melatonin levels. In summer, nights are short, thus the duration of the melatonin "signal" is short. In winter, nights are long, thus the duration of the melatonin "signal" is long. The duration of the melatonin signal is the cue that the circadian clock (this is in mammals only) uses to detect season, i.e., the changes in photoperiod (daylength) - information important for timing of seasonal events, e.g., molting, migration, hibernation, reproduction. Humans are only mildly seasonal - our ancestors about 70 million years ago were living in little holes in the ground, were tiny, were nocturnal, were seasonal breeders, and were hibernators. Some traces of our ability to measure photoperiod are retained in Seasonal Affective Disorder (SAD). It is almost a form of hibernation.
Phase-disorders of the circadian clock can have a similar effect by tricking the melatonin signal (or the reading of the signal by the clock) into believing it is always winter, thus time to be depressed. Lithium treats depression by affecting the period (thus indirectly phase) of the circadian clock (both in vivo and in vitro). In bipolar disorder, manic episodes are characterized by phase-advances and depressive episodes by phase-delays of the diurnal sleep-wake and activity patterns. In a way, phase-delayed people are constantly in the depressive phase of the bipolar disorder.
Trying to regulate sleep-time with melatonin can be tricky. If you are phase-delayed, thus producing melatonin in summer from 2am until 10am, if you take a melatonin pill at 10pm in order to go to sleep earlier, your clock will see a winter-like melatonin signal of 12 hours duration (10pm-10am) and will make you depressed within a couple of days.
Instead of buying a $500 light-box, you can, for much less money, build your own for a fraction of that money. You need a piece of board, 3-4 strong neon lightbulbs, balasts, a switch, a plug, and some wires. An hour of fun, and you have an apparatus that is just as good and effective as the hifallutin corporate gizmo. Use the light box, but also, when you first get up in the morning, immediately go out in the sunlight (that is thousands of lux of light energy, compared to hundreds from a lightbox) for a jog with your dog. If you do not have a dog, buy one - that will force you to go for a walk early in the morning. Well-scheduled meals also help.
Talk to your doctor about getting off anti-depressants. They tend to not work for circadian-based depression and may just mask the symptoms (i.e., you "feel" good while your body is falling apart).
Do not use melatonin supplements. Do not use alcohol - it may make you fall asleep fast, but the sleep will be shallow and erratic and you will wake up feeling lousy instead of rested.
Caffeinated drinks are fine, except during the last 2-3 hours before your intended bedtime, at which time a warm glass of milk may be better. Make a routine in the evening. The last 2-3 hours before bedtime stay out of the bedroom (bedroom is only for sleep and sex), and switch off all the screens: no TV, no computer, no gameboy. Reading a book while sitting in an armchair in the living room is fine. Just sitting on the porch and thinking will help you wind down. As the evening progresses gradually turn down the lights. Once the bedtime arrives, go to the bedroom, go to bed, switch off the light (pitch darkness) and go to sleep if you can. If you cannot, get up, but keep your lights dim, still no screens, no caffein, no food.
If you need to go to the bathroom in the evening or during the night, do not turn on the light. Can't you find your vital organs in the dark? If neccessary, a very dim nightlight (or indirect light from the hall) is OK.
If you wake up in the middle of the night, do not get up or switch on the light. Have sex instead. Hopefully your partner will enjoy being waken up by your kinky activities. You will both crash into pleasant deep sleep afterwards. If you do not have a partner, just do it yourself without switching on the lights (as I said, you can find your vital organs in the dark).
Of course, all of the above are the strategies to shift your clock to a "socially accepted" phase. But you are not crazy or sick. It is the societal pressure to get up at a certain time that is making you sick. Try to get a job that fits your natural schedule. Work at night, sleep during the day (in a pitch-dark, light-tight, sound-proof room) and enjoy life in all its quirkiness.
New blog on circadian rhythms, sleep etc.:
http://circadiana.blogspot.com/
http://sciencepolitics.blogspot.com/2005/01/next-tangled-bank.html
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