“…The lasting nature of symptoms in this subset of individuals with conversion disorder may reflect recruitment of a phylogenetically older mechanism of managing threat and danger when phylogenetically more recent mechanisms (for example, resolution of difficulties by flight, fight, or verbal negotiation) have failed or been blocked (Porges, 2001). This phylogenetic explanation is consistent with two centuries of clinical observation, where conversion symptoms have been noted to be associated with strong emotions, intolerable relationship predicaments, or situations that threaten the individual's physical or psychological integrity (Carter, 1853;Craig, 2001;Janet, 1889;Kozlowska, 2001Kozlowska, , 2005Ludwig & Lexington, 1972;Roelofs & Spinhoven, 2007;Seltzer, 1985;Taylor, 1986).…”