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Perceptual chronomter tells you when time slows down

Perceptual chronomter tells you when time slows down


Ladyada’s Ranting featured this very simple yet completely awesome project from a forum member, Magician13134 explains –

So, what is a perceptual chronometer? It’s basically a device that flashes numbers very quickly on an LED matrix or a 7-segment display. The human brain isn’t able to make out the numbers since the LEDs forming the number flash, then the LEDs invert (the ones that were on go off and vice-versa) too quickly to make out what they are. Then, during a life-threatening or adrenaline filled situation, if the brain is able to “slow down time”, you can read the numbers.

Inspiration came courtesy of Michio Kaku’s BBC documentary, “Time” –


Even if you never notice reality slow to a crawl, you could always pin a chronometer to your lapel for a very original conversation starter.

Source and PCB available over @ – Perceptual chronometer/Digg Button, and PCB success again!

14 thoughts on “Perceptual chronomter tells you when time slows down

  1. Mads Høbye says:

    What if you wave this thing in the air arent you going to see it eventhough you are relaxed?

  2. Collin Cunningham says:

    You’ve got a point there. I imagine motion could enhance legibility – but of course, revealing the number isn’t the actual goal here.

    … unless we’re considering the video’s test subject in freefall

  3. POV says:

    The thing is that even if it isn’t moving fast a quick glance across it would reveal the numbers. I remember going to Disney world when I was about 6 and they had a set of LED’s set up to show the concept of Persistence of Vision. When you looked at them they seemed to be a column of red lights on constantly, but when you looked from the left side to the right you would see simple pictures were being displayed. So unless you are staring right at this and not looking away you’re not really proving any change in time perception. You would have to be able to open your eyes and be looking directly at the display to counter the POV effect. Only then would you be able to detect a change in your perception rate.

  4. Anonymous says:

    “The thing is that even if it isn’t moving fast a quick glance across it would reveal the numbers.”

    you can do this anywhere. try glacing back and forth at car rims on the highway. normally they are a blur, but for a split second you can see them more clearly by glancing at them.

  5. Collin Cunningham says:

    @Aaron – thanks for that article. Oddly enough, for me it seems to concrete the view it opposes even more. near the end of the piece –

    “Instead, such time warping seems to be a trick played by one’s memory. When a person is scared, a brain area called the amygdala becomes more active, laying down an extra set of memories that go along with those normally taken care of by other parts of the brain.”

    I believe that our perception is our reality – this ‘double-datarate’ memory activity clearly marks a strong change from our usual thought processes and subsequently our perception of the events. If part of experiencing the normal passage of time is recording a ,normal, amount of memories, then during these heightened moments of awareness we are experiencing something substantially enhanced. Writing off a dramatic temporal change in brain activity as merely “laying down an extra set of memories” is missing the point. As is the nature of our media documentation and linear communication – all we have of a moment passed is a memory.

    “In this way, frightening events are associated with richer and denser memories,” Eagleman explained. “And the more memory you have of an event, the longer you believe it took.”

    I think David Eagleman could consider his own subjective experiences a bit more as an important part of this experiment.

  6. Kellin says:

    It’s similar to the “time flies when you’re having fun” concept, and how the opposite is also true.

    And on top of that, Eagleman’s experiment, I think, took the wrong approach. First, it only considers altered time perception as memory compared to an external perspective. In my experience, I have at times felt time slow down or sped up as I was experiencing it, not seen it from the outside and remembered it having felt slower.

    In my opinion, they didn’t properly recreate the situation they were emulating. Like Eagleman himself said, “I knew it was safe” – no doubt bungee jumping and rollercoasters are scary as hell, but there’s an element to starting to roll an intersection only to have a car from nowhere speed through the light just shy of your front bumper that just isn’t present in a situation you know is designed to scare you.

    On top of that, a perceptual chronometer is an arbitrarily introduced factor – in other words, it risks a placebo effect. Even in an otherwise properly designed situation, a subject deliberately diverting their focus could easily impact their perception and therefore alter the effect.

    The problem is largely due to the complex and minute balance that comprises human perception, not to mention the fact that, as perception is sensory input processed through the collected memories, every individual’s perception will differ somehow from the next. The experiment focused on the generalities and that is a good start but it looks like the case is closed as far as BCM is concerned.

    For what it’s worth, I’d like to contribute my experiences. I am an avid music nerd, and I almost always have something playing when I can. Also, between years of playing the viola and singing and hours of toying with the speed dial on my turntable – which cannot decide which direction is speed up and which is slow down – I’ve got a pretty keen ear for pitch. I tend to notice minute differences even if my focus is totally somewhere else. So when I notice a song is playing slower or faster than normal I mean it on no uncertain terms. Unless it’s some weird Pocahaunted-type creepy-freak-folk or noise music that uses a lot of off-notes and I’m not really familiar with it.

    My best example, however, involves conditions entirely different from the whole fear mechanism. I’d been up all night and downed a few pots of coffee, and as I was driving home I was positive that for a good twenty minutes everything was a little sped up. I know it’s not really the same situation, but it’s a similar effect. I’ve actually had a few friends corroborate on it… anyone else have anything like this happen?

    It would be cool to learn more about this effect, if there was a reliable way to reproduce it, it would open the possibility for use in biofeedback. You know, how people can train themselves to slow down their heart rate on command, things like that. Imagine being able to willfully slow your perception of time…

  7. Curious says:

    Or does the eye retina open up allowing more light to enter into the optic nerve, which allows the falling guy to see the numbers more clearly?

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