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Preception of time on a Clock.

  1. Oct 5, 2009 #1
    I have noticed that when one looks at a stopwatch or timer, which counts up or down respectively. if you watch the time being displayed continuously on the clock it seems smooth and uniform. Though if you watch them change, then close your eyes and open them in the middle of the change, the first viewed number seems to stay up much much longer.

    So as an example, if we look at a digital watch, the seconds position increments at a given rate of one per second. If we watch this for a few increments we get a feeling for how long each increment should take. Now if we close our eyes with that feeling, and we open them between an increment it seems as if our perception for the time of that increment is actually much slower than it really is.

    I hope I explained this well enough. Its not the easiest to explain. Id like to know why this happens.
  2. jcsd
  3. Oct 6, 2009 #2


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    I've noticed this effect in lots of situations besides those involving watches. I just sort of assumed that my internal clock, which doesn't work properly (maybe due to my ADD), had to recalibrate itself to match reality. It's an interesting question.
  4. Oct 6, 2009 #3
    I know exactly what you are talking about! I have my own theory:

    When you have been watching a watch (<-ha) for a long time, you grow very accustomed to the time interval that should pass before the next "tick". Following such a pattern is easy, uninteresting, and requires little focus or energy to process.


    When you look at a watch for the first time, it is impossible to know how far through the current "tick" it is. Essentially, it could turn anywhere from instantly, to a full second later.

    My theory is that you subconsciously make the assumption that you looked about half way through the interval. When it turns before you expect, you disregard it, because the whole event happened too fast for you to think about it critically, but when it takes longer than expected, you notice it. It's like bracing for a punch that doesn't happen right away. It's awkward.

    Also, the whole process of thinking about when the first tick will happen takes more brain power than once you've settled into a pattern, so time sort of slows, like when you merge onto a freeway. On a 100 mile trip, your merging onto the freeway for less than 1% of the trip, but more than 1% of your memory of the trip is devoted to merging onto the freeway, because that process was more interesting than coasting in the left lane for the other 99%.

  5. Oct 6, 2009 #4


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    When you open your eyes an look at the clock you are waiting for it to change, and so you are reprocessing the image of the current number very rapidly - it becomes a high priority thread in computer terms.
    When you have the numbers flicking past your brains gets used to the period of them and only bothers to update it's view of them less frequently.

    edit. Archosaur's freeway analogy is exactly right - it's also why people have crashes on long flat empty roads, as less and less happens on the road ahead your brain assigns a lower an lower priority to watching for things on it.
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