Delayed Sleep Phase Syndrome OR The Man with Two Brains

After a particularly stressful period in my life back in 1996 I started to develop problems that my doctor had labeled as depression. I would find myself being unable to sleep at night, having problems getting up in the mornings, and forgetting even the first names of work colleagues I had worked with for years. Only after several years did I notice there was a seasonal overlay to these problems. They tend to happen most in the winter, with some winters being worse than others, for reasons that are still not clear. And at the same time as I latched on to SAD (Seasonal Affective Disorder) and started experimenting with Light Therapy I was also diagnosed as having Auto-immune thyroid disease and low thyroid function. Treatments for both were mildly helpful, but the problem persisted. My doctor continued prescribing antidepressants even though after about 8 years (8 years!) I decided their effect was also, in fact, marginal.

Then about a year ago I learned of a condition that actually described my problem quite well. Delayed Sleep Phase Syndrome, or DSPS. In DSPS, people seem to have the onset of sleep delayed until 3 or 4 in the morning. A period of sleep then follows, which in my case is usually about 7 hours, so I typically might wake at about 11. But this sleep is not refreshing at all and it might take another hour before I can really get out of bed and get moving. When I visit the bathroom I am met in the mirror with a red, blotchy face, especially around the nose and eyes. I now suspect that this is caused by histamine, a hormone that plays a role in promoting wakefulness.

In normal people, in the last 2 hours of sleep, cortisol levels rise markedly and this period is also associated with REM sleep and dreaming, functions that are thought to promote organization of knowledge and memories and thoughts... i.e. higher brain functions. People deprived of REM sleep eventually become disorganized and dis-oriented, so REM sleep is considered to be very important. In most people, a 7 or 8 hour sleep period is followed by a period of activity during the day, with a progressive slowing down towards the end of the day, followed of course by the start of the next sleep period.

In people with DSPS, the period of intense wakefulness happens at night and the sleep period is not followed immediately by a period of intense activity.

This describes me quite well. In fact I am physically awake at 11 am, but mentally still asleep. At about 4pm (say) as daylight begins to fade, I can get very tired and sleepy, but of course sleep is not always possible, especially if at work. Rest is about as much as you can do. If I do get the opportunity to sleep it is usually a short sleep of perhaps one or 2 hours, but is incredibly refreshing. I wake up and finally have the energy and motivation to do things that I have been lacking all day. Unfortunately the energy boost is short lived so by midnight, physical exhaustion is back, but mental activity remains high until 4 or 5 in the morning.

What is going on here? Well, I have not been able to get a proper diagnosis or help but here is what I think is happening.

My feeling is that, when I am in this DSPS condition, I am not getting the 2 hours of REM sleep and my cortisol levels are low in the morning instead of being high. This means I have a depressed mental ability for most of the day. So although my lower brain is working and controlling my limbs and my physical being and I am walking around with the rest of the world, my higher brain is in fact only just about ticking over. It might just as well be fully asleep sometimes, because in the nadir of this condition I am mentally capable of nothing in the mornings or afternoons. In the late evening my lower brain is winding down my physical body, but my higher brain is only just waking up. Hence I am the main with two brains, each running on a different bio-rhythm. It is no wonder that I feel like I am only half my normal self at this time!

Because I get the boost in energy levels in the early evening, I believe that I am getting my circadian boost of cortisol from about 7pm, reaching a peak at about midnight. I very often am physically exhausted at this time, being incapable of any physical activity, yet totally unable to sleep. The mind is too active. And I believe that it is primarily the action of histamine that is waking me up in the mornings, judging by the bright red blotches on my face that will go away as the day progresses.

Now there is a family connection here. My mother, in her later life, stopped working and would often be asleep until late morning and describer herself as feeling pretty useless. Yet my father, who used to work at nights, would come home to discover that she had been sitting up all night, intensely listening to the radio. She also had other problems which fortunately I do not have, but I do think that there is an inherited characteristic here. Which leads to an interesting question. Debilitating as this condition is to the suffer, why has it survived? Does it confer a biological advantage? And is the reason that this tends to come on the winter somehow significant? I believe it is, and here is why.

The life we lead today is nothing like the life our ancestors led. It is their lifestyle needs that shaped their biology and in particular, gene characteristics that conferred a biological advantage. So what can possibly be so biologically advantageous about DSPS? Well actually, I think it is quite obvious.

One of the most important problems for our ancestors that migrated over millennia out of Africa to the northern and southern hemispheres would have been how to survive those long winter nights. Hypothermia is a killer even today. It would have been a major killer too for our ancestors. At night, when we are asleep and our body temperature drops and we lose consciousness during sleep. If we get too cold, we could easily die. So being awake and keeping that body temperature up, whether by keeping a fire going or just by being awake and being active, might be the difference between life and death. As hunter gathers, the human population in winter time has no need to be particularly active. Hunting is difficult and energy consuming. Better to live on those starchy foods put aside for the winter (is this sounding familiar?) and conserve energy by being relatively inactive. No need for much cunning in the wintertime (a higher brain function). And what better time to sleep than as the sun is coming up and temperatures will again be rising and not falling. So I am living out in this modern world, a pattern of behaviour that kept my ancestors alive but makes my life as IT Manager quite hellish in winter.

It is interesting to ponder why "depression" is so closely related to "stress". Why on earth did such a situation arise, and what possible benefit could it be to the species. My condition almost certainly arose after a very stressful life event, as indeed was the case with my mother. Perhaps the evolutionary story above is the clue. The stress of winter survival would certainly be a real stress for our ancestors and its onset could have triggered this potentially life saving condition. Its just that our bodies are driving by chemical signals and there is not much to distinguish psychological stressors from physical ones.

In due course, we may evolve out of this situation... but that is little comfort for me today.