http://en.wikipedia.org/wiki/Fight-or-flight_response
The fight-or-flight response (also called the fight-or-flight-or-freeze response, hyperarousal, or the acute stress response) was first described by Walter Bradford Cannon.
His theory states that animals react to threats with a general discharge of the sympathetic nervous system, priming the animal for fighting or fleeing. This response was later recognized as the first stage of a general adaptation syndrome that regulates stress responses among vertebrates and other organisms.
Immediate physical reactions associated with a preparation for violent muscular action. These include the following:
- Acceleration of heart and lung action
- Paling or flushing, or alternating between both
- Inhibition of stomach and upper-intestinal action to the point where digestion slows down or stops
- General effect on the sphincters of the body
- Constriction of blood vessels in many parts of the body
- Liberation of nutrients (particularly fat and glucose) for muscular action
- Dilation of blood vessels for muscles
- Inhibition of the lacrimal gland (responsible for tear production) and salivation
- Dilation of pupil (mydriasis)
- Relaxation of bladder
- Inhibition of erection
- Auditory exclusion (loss of hearing)
- Tunnel vision (loss of peripheral vision)
- Disinhibition of spinal reflexes
- Shaking
To be honest, you have to be pretty scared to suffer all of those in one go - and incredibly self-aware to recognise all of them (which would tend to suggest you still had mental capacity 'spare' to do something useful about it!).
But the one you're most likely to suffer from is the 'tunnel vision', and the way you'll suffer it is by keeping your concentration on whatever it is you're scared of.
In typical riding terms, this is likely to be an extremely hard object - wall, tree, vehicle - on the outside of the corner you're heading into.
Of course, where you look is - usually - where you go, so with vision firmly locked onto the very object which (if given a choice) you'd definately choose not to hit . . . you hit it. Of course, it's too late for 'flight' (unless it's a low wall), and you can't fight an oncoming vehicle (well, not for long, and not often with much chance of winning).
Keith Code has covered 'survival reactions' thoroughly in Twist of the Wrist 2.
http://www.superbikeschool.com/news/press-coverage/bike_this_man.php
SURVIVAL REACTIONS are the involuntary adjustments your body makes in situations that it feels are dangerous. "The body isn’t smart," says Code. "It’s only interested in right now." Survival reactions are bad. They make you brake too hard, turn in too early, tense up, get tunnel vision, chop the throttle and do a host of other things that interfere with good riding. With practice and skill they can be defeated.
However, I'm not sure that the way it's described there - in particular 'defeating' those reactions - is the best way of thinking about this.
So, perhaps we should 'enlarge' the fight or flight choice?
To me, fight or flight suggests two arrows: one head-on forwards, towards the 'fight', while 'flight' is directly behind us - an impossible task!
Instead, I suggest we had two 'sideways' options, to make a set of four arrows:
We'll call these arrows 'Escape' and 'Evade'.
Any of you who've spent time in the military may recognise the term, as it's used for the training given to aircrew who are likely to be downed behind enemy lines; evade capture and escape from captivity.
For us, as riders, they perhaps give a better idea of how the 'fight or flight' responses can be mastered. We can avoid the situation, or we can evade it getting worse.
Let's return to the corner with the wall/tree/vehicle: on the approach we put the 'avoid' into action by looking and planning, but - more importantly - we also are prepared for likely eventualities (it's not a big secret that tight bends are often followed by a bend the opposite way, that blind corners tighten, or that they can hide oobstructions). Being prepared means you've already taken care of some of the reaction time you'll need. You can even mentally rehearse the actions you'll need to take. If 'it' happens, then those actions go 'live' - you evade the danger.
Fight or flight? Nope, Escape and Evade!
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