I’m on holiday this week so I’ll be reposting a few articles from the old WordPress incarnation of Not Exactly Rocket Science. Stay with it though – these are five good’uns.
In The Matrix, when an agent first shoots at Neo, his perception of time slows down, allowing him to see and avoid oncoming bullets. In the real world, almost all of us have experienced moments of crisis when time seems to slow to a crawl, be it a crashing car, an incoming fist, or a falling valuable.
Now, a trio of scientists has shown that this effect is an illusion. When danger looms, we don’t actually experience events in slow motion. Instead, our brains just remember time moving more slowly after the event has passed.
Chess Stetson, Matthew Fiesta and David Eagleman demonstrated the illusion by putting a group of volunteers through 150 terrifying feet of free-fall. They wanted to see if the fearful plummet allowed them to successfully complete a task that was only possible if time actually moved more slowly to their eyes.
The task was deceptively simple. They merely had to read two numbers that were displayed on a wrist-mounted machine called a ‘perceptual chronometer’. Like a clunky digital watch, the device was programmed to show two numbers, but the catch was that the glowing digits were rapidly alternated with their negative images, where the area around the number is lit.
As the two images flicker more and more quickly, there comes a sudden point where they blur into a single uniform square of light. At this point, the rush of visual information overwhelms the brain of the volunteer, who is unable to resolve the two images apart.
The trio of researchers tuned the device to each volunteer’s threshold of resolution – the point where they only just failed to read the numbers. They reasoned that if a scary experience really made time slow down for the volunteers, even by a tiny amount, the flickering numbers should slow down enough to pop out of the blur. The effect should be like a slow motion camera, resolving the blur of a buzzing fly into individual wing beats.
To provide the necessary fear, Stetson took his volunteers up a SCAD tower (Suspended Catch Air Device) where they were strapped to a harness and dropped from a height of 150 ft onto a safety net. As they plummeted in free-fall, they had to try and read the numbers flashing from their wrists, while an eagle-eyed experimenter watched from the top to rule out those who kept their eyes completely shut.
The volunteers failed. In fact, they read the numbers just as inaccurately as a control group who did the same task while staying on the ground. Neo, they weren’t. Unlike the slowed bullet-time of The Matrix, a person’s perception of events in time doesn’t speed up when danger looms.
However, the volunteers did have a distorted view of time during their fall. Before they ascended the tower, Stetson asked each volunteer to reproduce how long a compatriot took to hit the net using a stopwatch. They were then asked to do the same after they’d had a go themselves. On average, the volunteers estimated that own experience took 36% longer than that of their fellows. Time didn’t slow down – the volunteers just remembered that it did.
Stetson and co believe that people lay down richer, denser memories when they experience shocking events. These ‘flashbulb memories’ include emotional content, which involves the brain’s emotional centre – the amygdala (see this earlier post about flashbulb memories in 9/11 survivors). As these memories are played back, their unusual richness could fool the brain into thinking that the recorded events took up more time than was actually the case.
Reference: Stetson, C., Fiesta, M.P., Eagleman, D.M., Burr, D. (2007). Does Time Really Slow Down during a Frightening Event?. PLoS ONE, 2(12), e1295. DOI: 10.1371/journal.pone.0001295
More on perception:
- How our skin helps us to listen
- The smell of danger – shocks help people discriminate between similar odours
- Pain in the eye of the beholder
- The Quantum Leap effect – creating a body-swapping illusion
- Blind man navigates obstacle course perfectly with no visual awareness
- Playing shoot-em-up video games can improve some aspects of vision
May 3rd, 2010 at 11:03 am
Ha! But how do you convince people who are sure they’ve lived through time slowing down?
Sometimes, when I’m very focussed while playing sport, the ball can appear to move more slowly towards me, allowing me to (feel I am) react(ing) faster.
So now, I need to make my brain believe that it is an illusory memory.
Does this mean I am better at sport than I thought???
May 3rd, 2010 at 12:47 pm
I had a similar thought while running a required 10 minutes cardio today in between my weight sets — “why is this the slowest 10 minutes I’ve ever experienced in my life?” Whereas if I’m chatting with a friend via computer or telephone time speeds up.
May 3rd, 2010 at 2:09 pm
“At this point, the rush of visual information overwhelms the brain of the volunteer, who is unable to resolve the two images apart.”
How do we know that the “rush of visual information” is actually overwhelming the brain, as opposed to some bottleneck in the receiving mechanism of the eye?
May 3rd, 2010 at 2:27 pm
That’s an interesting point because if it is some physical maximum frame rate of sorts, above which the eye cannot distinguish images, then the experiment would be testing whether or not the physical restraints of the eye can improve in a high stress/fear situation, not whether the brain can necessarily process and respond to information faster.
May 3rd, 2010 at 3:30 pm
I also suspect that this test setup was flawed. Some aircraft simulators are sped-up to compensate for the lack of “pucker factor” that a human pilot would experience in a real cockpit.
I don’t have the citations handy, but I think Euclid Holleman looked at this in the mid-70s at NASA. I’ve also heard this called “above real-time training” if you want some search terms.
Interesting that they estimated a 36% change, because the flight simulator folks seem to use 40% as a rule-of-thumb.
Maybe those researchers should look at flight data from actual aviation emergencies (with real fear, logged input and output data, and much more complex cognitive tasks than reading a number.)
May 3rd, 2010 at 9:06 pm
That is quite an interesting caveat brought up by earlier commenters; if it’s the higher cognitive centers in the brain that are speeding up their processing, you wouldn’t necessarily see any change in the output of V1, the primary visual cortex, which is the likely limiter for persistence of vision. It’s incredibly optimized already.
Anyway, interesting to see some sort of real data on this! They’ve successfully eliminated one possible region that could help explain the effect.
May 4th, 2010 at 12:50 am
Who can concentrate on a wrist display when falling from a great height?
I think it would be better if the display were a large one underneath the net. That is where you need to be looking for maximum scare value (and presumably maximum time-dilation.)
May 4th, 2010 at 11:36 am
I think the ideal task would be one where the person is responsible for making the right decision quickly to avoid harm to themselves. Of course, it may be hard to design such a test.
May 4th, 2010 at 10:31 pm
Sometimes in a crisis, there seems to be more time to make a decision and react. That’s if I can see it coming. On the other hand, physical shocks like suddenly falling through a floor happen way too fast to react to, and I recall that we fall a body-length in about 1/5 second. It’s an interesting question.
There may well be a training effect. After some training in sparring, many years ago, we seemed to get faster at reading situations and choosing a response. It would be interesting to design an experiment based on reaction time…. Oh, hell. Perception seems faster, too.
May 5th, 2010 at 5:30 am
#7. MW Says:
“Who can concentrate on a wrist display when falling from a great height?”
I can. I’ve fallen a mile over 2000 times, keeping an eye on a wrist mounted altimeter. It is amazing how much a skydiver can accomplish in 30 seconds of free-fall. It doesn’t take an emergency for time to slow down – remember, “A watched pot never boils.” On the other hand, try running to the bathroom for a bowel movement during a TV commercial. The next program segment is half over before you can get back!
I’m bothered by the headline on this article: Time doesn’t actually slow down in a crisis. Almost a silly statement. If time actually slowed down for the person in crisis, we’d all be out of sync with one another. Maybe it averages out, since we all face a crisis now and then. :o)
And I think the experiment was flawed because the test subjects weren’t really all that “scared” – they knew the experimenters weren’t going to let them fall to their deaths. Crisis diminished.
The question should be, “Does time seem to slow down in a crisis?” IMHO, it’s a definite “yes”. Our perception of time certainly changes depending on our circumstances at the moment.
May 5th, 2010 at 12:34 pm
Still there’s the problem of testing whether we actually think faster in a crisis, or if it only seems so in retrospect.
May 6th, 2010 at 7:25 pm
I’m wondering how they managed to convince enough subjects to participate in an experiment where they were thrown off a 150′ tower.
July 7th, 2010 at 11:38 pm
In my opinion time does slow down when we think faster. I was in a car accident and I specifically remember the air bag opening up in slow motion like a time lapse film of a flower blooming on the discovery channel. It had a cross hair right in the middle of it. I also remember (previous to the airbag opening) thinking about what parts of my body were the most important to protect. I decided I needed to cover my head with my hands then I decided that it would be better to see things coming at me so I could duck out of the way…so i moved my hands away from my head. I remembered seeing the grass coming by the window then the airbag opened. Then I saw it retracting back slowly and I wondered why it was retracting back. Anyway I made a theory from it. Arts theory of time. When we are young we think faster and summers seem to last forever and as we get older we slow down and time seems to fly by. Ever been in a hurry to get someplace? Seems like it takes forever. and animals??
July 7th, 2010 at 11:40 pm
Oh yea why do we think animals think at the same speed we do? They might think twice as fast such that their day might seem to be twice as long