However, using handgun loads that generate high pressure waves, we have observed instances of incapacitation in under 5 seconds without a direct hit to the CNS or supporting bone structure. Since we do not believe incapacitation this rapidly can be ascribed to bleeding, there must be another mechanism.
Emotional Fainting: An Involuntary Psycho-physiological Mechanism of Collapse
The unexplained magic of "energy transfer" is usually credited when a person immediately collapses unconscious after being shot in the torso with a handgun bullet. How else could someone be so quickly and decisively incapacitated, especially when the bullet didn't damage central nervous system organs, and the speed in which incapacitation took place precludes incapacitation by blood loss?
If you're a bullet company, you want people to believe that your product possesses unique powers to make bad guys instantly collapse. Energy transfer is popular belief, and you're going to tell your customers what they want to hear, despite the fact that there's no evidence whatsoever to support your claims or your customers' beliefs. If that's what the majority of your customers want to believe, then you're going to tell them that your bullets transfer more energy, and they do it faster and better than any other brand.
But if energy transfer isn't a mechanism of incapacitation, what is it that causes people to immediately collapse unconscious when other factors are ruled out?
In the last issue of Wound Ballistics Review, Fackler tackles this difficult question.¹ He identifies and describes a psycho-physiological mechanism of unconscious collapse called Emotional Fainting.
Fackler refers to Guyton2, and describes Emotional Fainting as "...[a] physiological mechanism, with an psychological cause, known as neurogenic shock — more specifically a type of neurogenic shock called 'Emotional Fainting'." Fackler explains:
"Strong emotions (such as fear) can cause widespread dilation of the body's blood vessels. These vessels have muscle fibers in their walls to allow them to constrict or dilate and thus vary blood flow as needed (in response to heat or cold, for example). The vessels are usually kept semi-constricted, but in Emotional Fainting, nerve impulses from the sympathetic nervous system can cause them to dilate completely. When this happens, the vascular capacity increases substantially and the blood available can no longer fill it. If the person is upright when this happens, gravity pulls the available blood into the legs and lower torso, starving the brain and causing the incapacitation."
Fackler continues:
"...the effects of Emotional Fainting, or some gradation of psychologically caused incapacitation (the gamut from surrender to Emotional Fainting), are either totally or partially responsible for much more of the observed reaction from bullet hits than is recognized. The practical result of this misinterpretation of the causes of reactions to being shot is overwhelming confounding effect on any attempt to compare efficacy of various bullets by observing, recording, and comparing the reactions of those hit."
Although Emotional Fainting appears to be a significant incapacitation mechanism, there's no evidence to suggest that any bullet characteristic (energy transfer, for example) triggers this reaction. While anecdotal reports of shootings seem to suggest that high-energy bullets are more effective in producing rapid incapacitation, these reports are tainted by the emotional bias of popular belief, which exaggerates stories that support the belief and suppresses those that do not.
Emotional Fainting is an unpredictable reaction and it is therefore unreliable. It is least likely to occur in people who are chemically intoxicated, psychotic, emotionally disturbed or acting with a single-minded determination to cause as much harm as possible before being stopped. It is probably most likely to occur in someone who is mentally unprepared to be shot or shot at.
Endnotes
Fackler, Martin L., M.D.: "Incapacitation Time." Wound Ballistics Review 4(1), Spring 1999; 4-8.
Guyton AC. Textbook of Medical Physiology, Eighth Ed., Philadelphia, PA. WB Saunders, 1992, p. 269.
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