How do we wake up just before the alarm goes off?

The answer in a column from the 80’s indicated that people were hearing minute sounds from the alarm clock, and were conditioned to wake up then. But I always wake up 5 to 10 minutes before the time I’m trying to wake up even with no alarm clock and at different times, such as differing early morning events, as opposed to a daily work schedule. And when I do use an alarm, it is the one on my cellphone which has no moving parts for me to hear. The old answer doesn’t cut it anymore, is there a new one?

The subconscious mind can keep track of time better than the conscious mind - Just a guess.

Link

I agree the last paragraph is outdated or possibly completely false as people claim that it still occurs while mechanical alarm clocks have all but disappeared. I don’t think anyone has ever proved a correlation.
Subconcious mechanisms triggered by other stimuli besides your clock,and/or the circadian rhythm theory are thought to be more likely now.
The question is, does the phenomenon exist at all? It doesn’t happen every single day like …err… clockwork. It may be that people mistakenly attach significance to the times it does occur.
There are other questions that need to be answered who, when, where, and under what conditions does it occur? Factors such as stress/anxiety are known to play a role in sleep/wake cycles. i.e. Insomnia and/or frequent wake times the night before a job interview or exam, etc…

It may be time for Cecil to update this one.

Could you possibly be hearing alarm clocks and general morning noises from nearby houses/apartments?

In my case it is the light coming through a crack in the drapes. When the time changed I awoke to the alarm clock for awhile. Now I wake up 10-15 minutes before the alarm.

I wanted an answer to this myself. When I was younger and used an old fashioned electric motor driven clock, I noticed there was a slight hum from 1 to 2 minutes before the alarm went off, probably because an internal switch was making a weak contact at that point. Evan after I switched to a digital clock some years ago, I was still waking up before the alarm, but now instead of a minute or two beforehand, it was usually about 10-15 minutes before.

I got curtains that would block almost all light from entering the bedroom, but it could still be detected as a faint glow around the edges. There are also local animals that maintain some kind of schedule for the noise they make, and some local traffic that I might be hearing. But I did begin to suspect that I was peeking at the clock while asleep, or possibly keep better track of time subconciously because of the changing LED display, so 2 years ago I began to turn the clock around so the numbers weren’t visible from the bed Unfortunately I wake up an hour or more before the alarm on most days, so it’s hard to see my results as reliable, but since turning the clock around, I rarely wake up a few minutes before the alarm anymore.

I think for any person, there are many different cues from the surrounding world that give an indication of time. And there are probably some people who can keep track of the time while they sleep without any external cues at all.

For a lot of us, there is no nearby house or apartment. My house is smack dab in the middle of a two acre lot, and I never hear anything from the neighbors but the cars.

I think the real answer lies in conditioning to sleep a certain length of time: even when I don’t have an alarm set, I wake up seven hours after I fall asleep; though on days off I usually roll over and go back to sleep. On work nights, this seven hour span is the same every night, so it’s not surprising that I almost always wake up within ten minutes of when the alarm will go off.

I assume we are speaking of this column: How come I wake up just before the alarm goes off? - The Straight Dope

My problem isn’t so much waking up shortly before the alarm, it’s that when I know that I have to wake up early, I can’t sleep that night. I know it’s all in my head, but the poor sleep coupled with the earlier time out of bed makes for a pretty tired day.

Yes, you are correct as referenced in post #3