Assessing the passage of time while asleep

In a normal night, I'll wake up once, maybe twice, for a wee. My bedroom is almost light-tight as I have roller blinds over the window, but I can sense the daylight though the opaque glass on my bedroom and kitchen door. Now, in high summer, it starts getting light soon after 4am, and so between 11pm and 4am, I have no clue as to what the time is should I wake between these hours. 

In the days when I'd keep a daily dream diary, I would notice that the quality and vividness of my dreams would become sharper throughout the night, with the best dreams in the morning. The ones I noted down upon waking up in the night would be less memorable than the ones captured around 7am, my normal time for rising.

But the question of guessing the time as I wake in the middle of the night got me thinking about my ability to assess the passage of time while asleep. So what I've started doing is this: I wake up in the night, and before getting out of bed, I guess what the time is. I base this on what had been going on in the dream prior to waking; what the narrative had involved, how many twists to the plot as it were. Having made my guess, I check on my phone. Sometimes I'm way out – last night, for example, as I woke up and estimated that the time is 01:30;  when I looked, I was surprised to see that it was already 02:55. Sometimes, I'm closer. Once or twice I've been right to within five minutes. 

If I were to come up with a rule of thumb here, I'd say the more memorable the dream, the better I can gauge the passage of time. While space distorts wildly in dreams (Poland morphing into the England, for example), time seems to pass at the same pace as in waking life. Having said that, I've had dreams where an anomalous logic loop occurs – the dream's narrative 'knows' information that logically could not have been known to me earlier (this dream is particularly fascinating).

So – question – can I improve the accuracy of my assessment of time's passing while I'm in the sleep state? I shall start logging this nightly in an n = 1 experiment, and I would be interested to see how readers get on with this!

When we are asleep, do our circadian clocks switch off? I am reminded of a story from the 1980s, when at the CBI National Conference in Glasgow. A colleague, well-known for his lunchtime drinking, returned to his hotel room for a nap. He woke with a start and looked at his watch – it was almost nine! Still dark outside (Scotland in November), so too late for a hotel breakfast – he dashed to the conference centre so as not to miss the opening speech of the second day, and arrived to find the venue closed, no one there. It was indeed nine o'clock – but the previous evening. Alcohol switches off certain brain functions when a drinker's fast asleep, including having a measure of the passage of time.

At this time of the year, waking up in daylight is no problem. An early start (for example, to catch the train to Gdynia last Friday) holds no terrors for me. No alarm clock – just leaving the roller blinds open so as to be woken naturally as the sun rises. But winter – no. I refuse to do early starts once sunrise is later than 6am.

Final point, mentioned to me by my brother a few weeks ago: "Hypnagogia – the transitional state from wakefulness to sleep, also defined as the waning state of consciousness during the onset of sleep. If you have trouble dropping off to sleep, don't do this, but I have become adept at noticing myself sliding into hypnagogia – having awareness of the moment. I welcome it, though insomniacs might find the very act of noticing its onset snaps them back to wakefulness, again and again.

UPDATE 18 July:

My training is getting results.

Guess          Actual

00:00           23:54

02:00           02:02

05:15           05:09

I'm getting better and better at this! Just a little bit of practice...

This time last year:
Summertime dreamland

This time three years ago:
Getting our heads around UFOs

This time six years ago:
Bristol-fashioned

This time seven years ago:
The imminent closure of Marks & Spencer in Warsaw

This time 12 years ago:
Along mirror'd canyons

This time 13 years ago:
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This time 14 years ago:
Komorowski wins second round of Presidential elections?

This time 15 years ago:
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This time 15 years ago:
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