?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=The+human+fear-circuitry+and+fear-induced+%0Afainting+in+healthy+individuals+%0AThe+paleolithic-threat+hypothesis+&rft.creator=Bracha%2C+Dr.+Stefan&rft.creator=Bracha%2C+Adam+S.&rft.creator=Williams%2C+Dr.+Andrew+E.&rft.creator=Ralston%2C+Tyler+C.&rft.creator=Matsukawa%2C+Jennifer+M.&rft.subject=Evolution&rft.subject=Psychophysiology&rft.description=The+Paleolithic-Threat+%0Ahypothesis+reviewed+here+posits+%0Athat+habitual+efferent+fainting+can+%0Abe+traced+back+to+fear-induced+%0Aallelic+polymorphisms+that+were+%0Aselected+into+some+genomes+of+%0Aanatomically%2C+mitochondrially%2C+and+%0Aneurally+modern+humans+(Homo+%0Asapiens+sapiens)+in+the+Mid-Paleolithic+because+of+the+survival+%0Aadvantage+they+conferred+during+%0Aperiods+of+inescapable+threat.+We+%0Aposit+that+during+Mid-Paleolithic+%0Awarfare+an+encounter+with+%E2%80%9Ca+%0Astranger+holding+a+sharp+object%E2%80%9D+%0Awas+consistently+associated+with+%0Athreat+to+life.+A+heritable+hard-%0Awired+or+firm-wired+(prepotentiated)+predisposition+to+abruptly+%0Aincrease+vagal+tone+and+collapse+%0Aflaccidly+rather+than+freeze+or+%0Aattempt+to+flee+or+fight+in+response+%0Ato+an+approaching+sharp+object%2C+a+%0Aminor+injury%2C+or+the+sight+of+blood%2C+%0Apolymorphism+for+the+hemodynamically+%E2%80%9Cparadoxical%E2%80%9D+flaccid-%0Aimmobility+in+response+to+these+%0Astimuli+may+have+increased+some+%0Anon-combatants%E2%80%99+chances+of+survival.+This+is+consistent+with+the+%0Aunusual+age+and+sex+pattern+of+%0Afear-induced+fainting.+The+Paleolithic-Threat+hypothesis+also+predicts+a+link+to+various+hypo-androgenic+states+(e.g.+low+dehydroxyepiandrosterone-sulfate.+We+offer+%0Afive+predictions+testable+via+epidemiological%2C+clinical%2C+and+ethological%2Fprimatological+methods.+The+%0APaleolithic-Threat+hypothesis+has+%0Aimplications+for+research+in+the+%0Aaftermath+of+man-made+disasters%2C+%0Asuch+as+terrorism+against+civilians%2C+%0Aa+traumatic+event+in+which+this+%0Ahypothesis+predicts+epidemics+of+%0Afear-induced+fainting&rft.date=2005&rft.type=Journal+(Paginated)&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.identifier=http%3A%2F%2Fcogprints.org%2F5035%2F1%2F2005_C.A.R_review_FEAR-CIRCUITRY-DRIVEN_FAINTS.pdf&rft.identifier=++Bracha%2C+Dr.+Stefan+and+Bracha%2C+Adam+S.+and+Williams%2C+Dr.+Andrew+E.+and+Ralston%2C+Tyler+C.+and+Matsukawa%2C+Jennifer+M.++(2005)+The+human+fear-circuitry+and+fear-induced+fainting+in+healthy+individuals+The+paleolithic-threat+hypothesis.++%5BJournal+(Paginated)%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F5035%2F