Speed Freaks: Tunnel Vision and Physiological Perception

Speed Freaks: Tunnel Vision and Physiological Perception

Paul M Pozzi Jr 1/30/2014

*** WARNING ***

Before anyone begins to read this, a disclaimer is necessary: DO NOT TRY THIS AT HOME. There is an exceedingly high likelihood that you will DIE or go to JAIL, lose your driver’s license, and have your vehicle impounded as evidence. In most states, exceeding the posted speed limit by double or 30 miles per hour, whichever is less, constitutes felony speeding. If you are caught, you will likely be charged with felony speeding, reckless endangerment, reckless driving, gross negligence, evading pursuit, resisting arrest, and several other violations of your state’s motor vehicle codes. Again, DO NOT attempt to duplicate this condition in the manner presented below.

 

So there I was: three in the morning on a Monday, rocketing southbound on US-101 back to Monterey from San Francisco. I was late. I was really, really late. My 72-hour weekend pass had expired four hours earlier and I was supposed to have been back on post by 2300 (11 PM for civilians) on Sunday night. I was speeding. I was really, really speeding. The last time I remember looking at the gauges on my motorcycle, I was doing somewhere on the dangerous side of 150 miles per hour near Edenvale. I think that was about when I started to notice that I couldn’t see my mirrors anymore. Normally, even when I was completely tucked in behind the windscreen, I could see mirrors in my peripheral vision. But since I was so late, and an invincible twentysomething, I kept that throttle pinned wide open. Then I noticed I couldn’t see the edges of the windscreen or even the lights of the gauges. When I came to my senses and realized how utterly stupid this behavior was (despite the rush I felt), I rolled off – slowly – and sat up. The first thing I remember being able to focus on was that orange needle against a white speedometer face coming down past 170, and I realized I’d just experienced tunnel vision. I was passing the exit for Gilroy, almost 20 miles and under seven minutes later.

A statute mile is 5280 feet. At 60 MPH, a vehicle is travelling 5280 feet per minute, or 88 feet per second (FPS). At 120, a vehicle is travelling twice that: 176 FPS. I figure I was probably doing close to 180 – just shy of the Japanese manufacturers’ gentlemen’s agreement of an electronically-limited 300 kilometers per hour (189 MPH) top speed for all their street-going superbikes. At that speed, my motorcycle and I were flying low, literally exceeding the maximum attainable speed of most helicopters and propeller-driven airplanes, covering an absolutely astonishing 264 feet every second. That’s nearly the length of a football field. In a second. I would’ve outrun everything CHP (California Highway Patrol) had except the radio.

Studies have suggested that humans are capable of normally processing approximately 13-15 frames per second of vision (Deering, 1998). It is estimated that the average human is comfortable processing information in a close-proximity moving environment, such as driving, at no more than 72 MPH. Currently, the accepted standard for the earliest phases of greyout is roughly 39 meters per second (NAMI, 1991), which is a precursor to true tunnel vision, where the human mind starts ignoring peripheral visual input in order to focus on survival (dealing with what is immediately in front of you) and what is referred to in aviation as g-LOC, or g-induced loss of consciousness. That would be where a human is physiologically overloaded by stimuli, environmental factors, or an extreme and prolonged adrenaline dump and momentarily passes out due to the brain focusing on survival of the body rather than providing sufficient blood flow, and thus oxygen, to the brain for sustainment of active cognitive processes.

Obviously, there are trained individuals capable of processing information effectively at these speeds, in controlled environments; otherwise we wouldn’t have such lavish extracurricular activities as low-altitude aircraft racing, professional or amateur automotive racing (on two wheels or four, and I’m including – reluctantly – NASCAR in this), but it should be highly stressed that these people are exceptions to the rule. While our eyes are capable of transmitting in excess of 200 frames per second (which means our optic nerves collect and transmit a picture to our brain in less than 0.005 seconds) (Brand, 2001), our minds subconsciously decide to process less than half of those images This is why we perceive seamless motion in even an old cathode ray tube television at a mere 30 frames per second (Brand, 2001). Depth perception, color acuity, and general visual clarity all fall victim to our brains deciding to ignore ancillary input in “fight-or-flight” mode, triggered by prolonged acceleration, massive adrenaline dump, or chemically-induced states of altered consciousness (Godnig, 2004, et al).

We’ve all been in a position at some point where we “saw red” or got so excited, scared, or physically traumatized that we briefly became wobbly-kneed, couldn’t focus properly, and making a life-altering decision such as “do I want scattered, covered, and smothered, or do I just want grits?” was all but impossible. The best course of action in such a situation is to take a few slow, deliberate breaths, back up a step or two cognitively, and repeat the thinking process again more deliberately. As any good tactical instructor will tell you: slow is smooth and smooth is fast.

And hash browns “all the way” is always the best choice.

References:

MF Deering, “Limits of Human Vision”, Sun Microsystems, 1998

US Naval Aerospace Medical Institute (NAMI), Naval Flight Surgeon’s Manual: 3rd Ed 1991, Ch 2: Acceleration and Vibration http://web.archive.org/web/20051123000128/http://www.vnh.org/FSManual/02/02SustainedAcceleration.html

Dustin D Brand, “Human Eye Frames per Second”, 2/21/2001, online, http://amo.net/NT/02-21-01FPS.html

Dr. Edward C Godnig O.D. FCOVD, 2004, The Police Policies Studies Council, online, http://www.theppsc.org/Staff_Views/Godnig/vision_and_shooting.htm

Alan A Stocker and Eero P Simoncelli, 12/2004, “Constraining a Bayesian Model of Human Visual Speed Perception”, MIT Press 5/2005, http://www.cns.nyu.edu/ftp/eero/stocker04b.pdf

 

1 thought on “Speed Freaks: Tunnel Vision and Physiological Perception

  1. Angela S Koch

    Wow. Your story is a great, yet terrifying, one. I have had an experience similar to yours as far as losing perceptual vision, but under far different circumstances. My experience was due to G-force on a roller coaster making me experience tunnel vision and even g-LOC in one circumstance. While our experiences were under different circumstances, they do share two similarities: speed, and probably a rush whilst our minds think we are in danger. Though I imagine you were in quite a bit of danger, either from an accident or from a commanding officer for being late. While your mind was unable to take in all of the stimuli around you, you were able to see what was directly in front of you. This concept to me is fascinating and I was completely unaware that people would lose peripheral vision at a certain speed. Something that I wonder about this is whether or not cutting out peripheral vision actually helps our minds to concentrate on what is only directly in front of us. I imagine it is. So maybe it could be possible to harness this idea and use it to help those that have over stimulation problems associated with autism or Downs syndrome.

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