The human fear-circuitry and fear-induced fainting in healthy individuals The paleolithic-threat hypothesis

Bracha, Dr. Stefan and Bracha, Adam S. and Williams, Dr. Andrew E. and Ralston, Tyler C. and Matsukawa, Jennifer M. (2005) The human fear-circuitry and fear-induced fainting in healthy individuals The paleolithic-threat hypothesis. [Journal (Paginated)]

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The Paleolithic-Threat hypothesis reviewed here posits that habitual efferent fainting can be traced back to fear-induced allelic polymorphisms that were selected into some genomes of anatomically, mitochondrially, and neurally modern humans (Homo sapiens sapiens) in the Mid-Paleolithic because of the survival advantage they conferred during periods of inescapable threat. We posit that during Mid-Paleolithic warfare an encounter with “a stranger holding a sharp object” was consistently associated with threat to life. A heritable hard- wired or firm-wired (prepotentiated) predisposition to abruptly increase vagal tone and collapse flaccidly rather than freeze or attempt to flee or fight in response to an approaching sharp object, a minor injury, or the sight of blood, polymorphism for the hemodynamically “paradoxical” flaccid- immobility in response to these stimuli may have increased some non-combatants’ chances of survival. This is consistent with the unusual age and sex pattern of fear-induced fainting. The Paleolithic-Threat hypothesis also predicts a link to various hypo-androgenic states (e.g. low dehydroxyepiandrosterone-sulfate. We offer five predictions testable via epidemiological, clinical, and ethological/primatological methods. The Paleolithic-Threat hypothesis has implications for research in the aftermath of man-made disasters, such as terrorism against civilians, a traumatic event in which this hypothesis predicts epidemics of fear-induced fainting

Item Type:Journal (Paginated)
Keywords:fainting, human evolution, war, combat, fear-circuitry, androgens, stress-induced disorders
Subjects:Biology > Evolution
Psychology > Psychophysiology
ID Code:5035
Deposited By: Bracha, H.S.
Deposited On:01 Aug 2006
Last Modified:11 Mar 2011 08:56


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