Internal Clocks

November 24, 2004 12:50 PM

Somewhat related to grumblebee's question below but not really: I have an uncanny sense of time. I never wake up to an alarm because I spontaneously wake up a minute or two before it goes off and reach out and shut it off. Also, If asked to guess the time after not having looked at a clock for a day, I am usually within 10 minutes or so. Firstly, what exactly is the "internal clock" and how does it differ among people? Secondly, is my behavior typical or is it at an extreme?
posted by vacapinta to Health & Fitness (18 answers total)

Me too, Vacapinta! If I've gone to bed sober, and not stupidly late, I always wake up just before the alarm. My ability to guess the time isn't as accurate as yours (usually + or - 30 mins), but only functions in the day time, so I've always figured I was somehow unconsciously able to tell the time by the position of the sun and the light. Worked after a few days in different countries and timezones. too.
posted by Pericles at 12:57 PM on November 24, 2004

I do the exact same thing almost every day, no matter what time the alarm is set to go off. It is indeed uncanny. I chalk it up to a visceral discomfort with the buzzer sound that manifests itself in a subconscious fear of it being activated. Either that, or I unknowingly look at the clock in my sleep. Anyway, I thought I was the only one.
posted by Succa at 12:57 PM on November 24, 2004

Me too! -/+ 5 minutes. In fact, at age 6, this go me up a 4am to see Neil Armstrong walk on the moon.

How is this possible?
posted by ParisParamus at 1:07 PM on November 24, 2004

I don't know if it's typical, but I do the same thing. Especially if I have something urgent in the morning. Works across timezones too.
posted by mosch at 1:08 PM on November 24, 2004

I'm another.. i never hear an alarm, don't wear a watch, and am accurate to the second about time.. short intervals are precisely accurate. i might be 2-5 minutes off in estimating that 6 hours have passed, but only a minute or so off if it's only 2 hours).

I'm a nurse, and accurate counting and timing of things like a pulse are a snap for me; and i've been challenged and tested on my accuracy repeatedly.

As far as i can recall, it's always been so, and changing time zones doesn't matter. I just know.. i don't have to check the clock to know what time it is.. ever.

I think of it as a knack for rhythm; are you a good dancer, too?
posted by reflecked at 1:15 PM on November 24, 2004

Another voice chiming in - I'm getting that this is not unusual. I do it too, works everywhere, day or night, +/- 10 minutes.

On preview - however I have no rhythm, alas.
posted by mygothlaundry at 1:17 PM on November 24, 2004

Here's a (maybe) helpful PDF. I didn't read the whole thing, and it's not all that well written, so caveat reader. It does however, highlight the two main models (Triesman, 1963 and Gibbon, Church and Meck, 1984) and discuss some really interesting experiments performed in the early part of the 20th century. It turns out that ambient temperature has a causal connection to subjective measurements of time. If you're in a cold room, your subjective measurement of time increases (i.e., a subjective minute is longer than a true minute) and if you're in a hot room, it decreases.

This is all I remember from a course in Sensation and Perception. Sad, really.
posted by zpousman at 1:21 PM on November 24, 2004

It might be unusual, but it was a trained thing for me. A friend of mine could tell the time within 15 minutes, and I thought that was neat. I started trying to guess the time and then verifying them, and in short order I could do the same thing. My high quality swiss watch stopped working a while ago, and I never got around to repairing it.

Playing MMORPGs (or really immersive games) or smoking weed throws my ability right off though :).

The real interesting thing is that I used to sleep like a brick, but since I started "counting" time, I'll decide I need to wake up at a certain time, and unfailingly wake up by my own a few minutes prior. That one took me aback, since I enjoyed my sleeping through alarms, any kind of noise, and once, even through a police chase and accident at 3am in my small 10 house or so street. It was weird waking up to a torn up lawn, fences broken, etc., and have no idea what occured.
posted by splice at 1:31 PM on November 24, 2004

I wake up right before my alarm, because I can hear the speakers turn on right before the alarm goes off.
posted by kenko at 1:41 PM on November 24, 2004

I do this too, including guessing the time of day or night.

It seems like the ability to wake at the same time every day could be explained easily by neurochemistry and circadian rhythms, but waking at a different given time simply by deciding when you'll need to wake up tomorrow seems to imply a subconscious awareness of passing hours.

In any case, here's an interesting paper on the biology of time.
posted by oraknabo at 1:43 PM on November 24, 2004

It's a learned behavior for me. When I was very young I read about a boy who woke up before his alarm clock and I started doing it.

There's a little click in some clocks just before it goes off and I wake up to that. Or I just think about what time I want to wake up in the morning, if there's no clock, and that does the trick. Even when I sleep in late I know what time it is when I wake up.
posted by Jim Jones at 2:16 PM on November 24, 2004

I used to have a room-mate who would wake me up every morning, and after a while I would wake up on my own just before she came to get me out of bed. When we eventually moved apart I discovered that I could set the alarm in my head before going to sleep (telling myself "tomorrow I have to get up at 8:00...no make that 8:15" for example), and I would wake up very close to that time. For about two years I relied on this method as my alarm-clock for everything; work, exams, transatlantic flights, etc. I very rarely overslept, and never when I had to get up for something important.

I don't do it anymore because I think I sleep better when I know that an alarm will go off. Most of the time I wake up just before it goes off though.
posted by Agent X9 at 4:01 PM on November 24, 2004

If I am well-rested, I do. If not, not, for the most part.
posted by stavrosthewonderchicken at 4:01 PM on November 24, 2004

I never use an alarm clock and I don't wear a watch. However if I am out in the garden, all sense of time evaporates like the morning dew off a ladybug's butt. Two or three hours go by and I feel like I am just getting started.
posted by Secret Life of Gravy at 4:58 PM on November 24, 2004

Wow, I'm completely the opposite. If I can see the sun I can make a reasonable guess--assuming I am geographically oriented and it isn't too close to noon. Other than that, I've been known to be off by as much as a couple of days.
posted by Grod at 5:40 PM on November 24, 2004

I am notoriously bad at estimating time. In grad school I read an article (no chance I can remember the authors) that indicated that people's estimates of elapsed time are based in part on the number of events that occur. That is, if you are sitting around with no interruptions for a period of time, you will estimate that a shorter amount of time had passed than if a few events happened during that period.

Time perception is an interesting phenomena that has been studied to death. I remember seeing an entire book that consisted solely of a bibliography of time perception studies...

I have a friend who can set a mental alarm clock to ensure she wakes up at a particular time. However, in introspecting, she indicated that if she's trying to wake up earlier than usual, she wakes up a number of times during the night and falls asleep if it is too early.
posted by i love cheese at 7:34 PM on November 24, 2004

I have a few friends with mental clocks, and from what I've heard, non-reliance on a watch sharpens your time sense, and use of a watch dulls it. One of my friends used to be able to get the time to something crazy like within 7 minutes of the actual time, but after getting a watch as a present, his accuracy went down to "getting the hour right".
posted by Bugbread at 8:21 PM on November 24, 2004

I am a night owl and unfotunately I work shifts. When I have to get up any time after 7.30am I'm fine, but I have an internal clock that tells me it's too bloody early to wake up at 5.30am and so have to have 5 alarm clocks to get me to rise! I try the mental alarm clock before I go to sleep (a mantra of "I must get up at 5.30") which helps to a certain extent by stopping me falling into a deep sleep. My problem is that I can't physically go to sleep before 11.30 pm and so I'm always knackered when on early shifts.

As for the rest of the day, I don't think I can tell the time that well without looking at a clock regularly - but I don't wear a watch so maybe I'm better at it than think...hmmm.
posted by floanna at 9:30 AM on November 25, 2004