The human fear-circuitry and fear-induced fainting in healthy individuals
- 218 Downloads
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 hardwired 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, may have evolved as an alternative stress-induced fear-circuitry response. Such a stable (balanced) 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 dehydroxy-epiandrosterone-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.
Key wordsfainting human evolution war combat fearcircuitry androgens stress-induced disorders
Unable to display preview. Download preview PDF.
- 2.Appenzeller O (1990) The autonomic nervous system: an introduction to basic and clinical concepts. Elsevier, AmsterdamGoogle Scholar
- 4.Bracha HS (2004) Neurorevolutionary (distal) etiologies of fear-circuitry disorders: Current perspectives and proposed directions for future research. Progress in Neuro-Psychopharmacology and Biological Psychiatry (in press)Google Scholar
- 7.Bracha HS, Ralston TC, Williams AE, Yamashita JM, Bracha AS (2005) The clenching-grinding spectrum, and fear circuitry disorders: clinical insights from the neuroscience/paleoanthropology interface. CNS Spectrums: Int J Neuropsychiatr Med 10(4):311–318Google Scholar
- 10.Ewald PW (1994) Symptomatic treatment (or How to bind The Origin of Species to The Physician’s Desk Reference). In: Ewald PW (ed) Evolution of infectious disease. Oxford University Press, Oxford, New York, pp 15–34Google Scholar
- 12.Klein RG, Edgar B (2002) The dawn of human culture. Nevraumont Publishing Company, New YorkGoogle Scholar
- 13.LeBlanc SA, Register KE (2003) Constant battles: the myth of the peaceful, noble savage. St. Martin’s Press, New YorkGoogle Scholar
- 15.Miller GF (2001) The mating mind: how sexual choice shaped the evolution of human nature. Anchor Books, New YorkGoogle Scholar
- 16.Morgan E (1990) The scars of evolution: what our bodies tell us about human origins. Oxford University Press, OxfordGoogle Scholar
- 17.Nesse RM (1999) Testing evolutionary hypotheses about mental disorders. In: Stearns SC (ed) Evolution in health and disease. Oxford University Press, Oxford, pp 260–266Google Scholar