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Process Hazard

Fighting Tunnel Vision - Vic Napier (USA) 2011

Vic Napier made his first jump in 1980 and has logged 2,100 skydives since. He holds an FAA Master Rigger certificate, operated No Excuses Rigging for ten years and has held USPA (US Parachute Association) Static-line, AFF (accelerated freefall instruction) and Tandem Instructor ratings. He earned an MBA in 2003 and is presently working on a PhD in Psychology. Here he shows we can improve how our brain works under stress.


Incident

It was the perfect kind of day that only the Arizona desert can produce. Not a cloud in a dark blue sky, temperatures in the 90’s, humidity in the teens, the smell of cactus blooms in the air and I was on my motorcycle at the end of a two hour ride from Phoenix to my home in Tucson. Less than a mile from my apartment a car made a right turn directly in front of me - a classic prelude to an auto-motorcycle collision. Naturally, I slammed on both front and rear brakes, and my eyes riveted on the exact spot on the passenger door promising to be my impact point. But then I did a very unnatural thing - I looked away from the car door towards the rear bumper. Although every fiber of my being was demanding that I stare at where I would hit the passenger door I looked to the left. The bike leaned in that direction, the car glided through its turn and I slid past the rear bumper by inches.

Survival

Wow, I thought, that was close. But why did I spend so much time staring at something I was sure to hit without doing anything more than listen to my tires squeal? As it turns out, for the same reason that skydivers stare at malfunctioning main canopies without doing much, or keep their eyes fixed on the objects they collide with when landing off the drop zone. We are hard wired to stare at threatening things - it’s an automatic reaction to dangerous situations that benefited our ancestors and our brains still carry it. It was a good survival tactic in the jungles and savannah where the human race spent most of its history, but leaves something to be desired in the modern high speed mechanized world in which we now live.

Our brain does amazing things when we are confronted with danger. Exactly how the brain recognizes danger is unclear, but when it does higher brain functions are left out of the loop. We don’t think in the normal sense; instead a primitive survival system takes over. Stress hormones called glucocorticoids are dumped into the bloodstream. Our liver, muscles and fat cells are instructed to convert all the nutrients they hold into glucose - our digestive system actually reverses itself to produce energy rich glucose instead of store it. Blood vessels throughout our body decrease in diameter and heart rate increases so all those stress hormones and high energy glucose reaches our brain and muscles in fractions of a second. Brain functions become quicker, senses become sharper, physical strength is boosted and reaction times decrease.

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Focus

Something very interesting also happens to our vision as well. Our perception of colors and shapes becomes more active and our ability to identify detail gets more acute because the cones and rods at the back of our eye become more sensitive to light and shape. At the same time our visual cortex (the part of our brain that processes signals from our eyes) becomes extremely active in order to take advantage of this increased sensitivity. This is one of the reasons for the illusion of time slowing during stress. Details that might take us several seconds to notice are perceived and memorized almost instantly. Time does not speed up or slow down - it just seems like it does because our senses suck up information at such an accelerated rate.

Most importantly for those of us engaged in high speed recreation, our visual field becomes narrower. We actually lose a good portion of our peripheral vision. We become so fixated on what our brain has identified as a danger that we are no longer capable of seeing things to our right or left. That is why I was so fixated on my impact point on the side of the car and why it seemed so unnatural to look for a path to avoid collision. My field of vision was so narrow that the impact point filled my awareness.

The same thing happens to skydivers facing a dangerous situation in the air. In a freefall emergency we often don’t realize how close we are to the ground because our peripheral vision narrows so much that we do not see the horizon engulfing us. That is why so many of our skydiving brethren fell to their deaths before the widespread use of AADs (Automatic Opening Devices). They fought malfunctioning mains all the way to impact because they never realized how close they were to the ground.

Weakness

This human tendency to visually fixate on dangerous objects combined with a narrowed field of vision also contributes to landing injuries. When we suddenly find ourselves landing off the drop zone or missing the venue on a demonstration jump we tend to look at the dangerous things that can hurt us instead of the safe place where we want to land. Because we steer where we look we can easily end our jump on something hard or sharp ensuring a trip to the hospital and a lengthy recovery before our next jump. This is why it is so important to consciously think about looking where we want to land - we tend to steer our parachutes where we look. We do the same thing with our cars, motorcycles and even as we walk.

Try this experiment. Get a long narrow tube an inch or less in diameter and maybe a foot long. A plastic pipe or the tube from a roll of wax paper or aluminum foil works well. Cover one eye and look through the tube in such a way that you have no peripheral vision and can see only one small object at a time. As you look through the tube pick on object to your left or right that fills your limited field of view. Keep looking at the object and walk past it in a straight line. You will need to turn your head and maybe your upper body in order to keep your eye on the object. Most of the time you’ll walk in a slight curve towards the object. Without the aid of peripheral cues most people will tend to walk toward the object they are looking at, even though they concentrate on walking in a straight line.

It is very hard to overcome these psychological and physiological reactions to dangerous events because they have worked so well to ensure the survival of our species. Maintaining an intense and narrow visual focus on a lion one spots in the brush is a very good survival mechanism. A very narrow field of vision eliminates distractions that might have caused our ancestors to lose concentration on running a spear through the heart of dangerous prey. Individuals with these traits had a higher chance of surviving encounters with wild animals, and their families and tribes had a higher chance of benefiting from both the increased safety in the immediate environment as well as the increased protein available to their diet. Our ancient humanlike predecessors who did not have these attributes had a lower chance of survival both individually and collectively - and a lower chance of passing their genes onto modern humans.

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Refocus

So we are stuck with genes that are not well suited to dealing with high speed emergencies. What can we do about it? Luckily we have a huge advantage - our brain, and its ability to learn and remember.

For skydivers this means adopting a plan to deal with emergencies and practicing that plan on a regular basis. For example, many first jump courses teach students to react to a partial malfunction by pulling both steering handles all the way down twice, then initiating emergency procedures by looking at the canopy release handle. Simply repeating that sequence of movements is enough to train your brain to do something besides stare at a malfunctioning canopy - the source of a threat. However you don’t have to wait around for Safety Day to hang in a harness in order to practice. There is no reason why you can’t sit in your easy chair in front of the TV, look to the ceiling, imagine you see a malfunctioning parachute, go through the motions of pulling steering handles and then looking to the right side of your chest and beginning your emergency procedures.

One of the reasons I was able to avoid colliding with that car was because of the braking and swerving practice I occasionally do in empty parking lots and deserted roads. I practiced swerving while looking where I wanted to go instead of where I was going. Skydivers can practice emergency landing techniques using the same principles. Make every landing an accuracy attempt. Pick a landing spot and do a downwind, base and final on every jump. Concentrate on your target, but sneak a peek at other canopies, the wind sock and people walking around near the target. Practice looking where you want to land instead of what you want to avoid. If you ever find yourself forced to land in a pasture surrounded by power lines and festooned with horse troughs and farm machinery the practice will pay off.

Training

Going through that simple series of motions requires neurons in your brain that control motor function (movement) to fire in a particular sequence. The more often you repeat that physical sequence the more “automatic” the sequence becomes. Amazingly, just thinking about making those movements stimulates both the neurons in the brain that controls those movements, as well as the neural pathways in the muscles that command the muscles to move. Just imagining doing emergency procedures is almost as good as actually doing them.

But that’s not all.

Practicing reactions to emergencies increases our confidence, and increased confidence lowers the stress response of our bodies when we face dangerous situations for real. Our field of vision is not as narrow as it might be otherwise and our tendency to fixate on a “fear object” is diminished. Because our brain is in a more relaxed state it is more able to dedicate resources to creatively addressing new challenges. You may not be the only off course skydiver landing in that power line surrounded field and decisions about S turns or braking might have to be made. Instead of simply reacting to a situation we are more able to manage our behavior by practicing the right thing instead of allowing our natural reactions to rule the situation.


Original article: http://www.vicnapier.com/MyArticles/Parachutes_Skydiving/fighting_tunnel_vision.htm

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