Alexithymia is a term introduced by Sifneos (1973) to refer to individuals who have difficulty in verbalizing symbols, lack an ability to talk about feelings, have an impoverished fantasy life and drab dreams, have difficulty describing and pointing to pain in their own bodies, tend to express psychological distress by focusing on external concerns and their somatic symptoms rather than on emotions, show an overconformity in their interpersonal relationships, have a reduced ability to experience positive emotions together with a susceptibility to poorly differentiate negative affects, and lack a productive, creative involvement with the world. This psychiatric syndrome was described by Sifneos (1973), who observed an impoverished fantasy life among psychosomatic patients, who, in comparison to psychoneurotic controls, showed a utilitarian way of thinking that considers other people to be objects to be manipulated (Marty & de M'Uzan, 1963).
There is evidence that highly humiliating experiences and experiences that are deeply and massively traumatic, such as being physically and verbally abused as a child, being a victim of repeated sexual assault (Zeitlin, McNally, & Cassiday, 1993), experiencing high levels of the affective, unpleasantness component of pain (Lumley, Smith, & Longo, 2002), having pain induced in an experimental setting (Kaplan & Wogan, 1977), having been imprisoned in a Nazi concentration camp (Krystal, 1968), experiencing traumatic events in the social environment (Krystal, 1988, van der Kolk, 1987), having a catastrophic and painful illness (Fukunishi, Tsuruta, Hirabayshi, & Asukai, 2001), suffering from posttraumatic stress disorder (PTSD; Zeitlin, Lane, O'Leary, & Schrift, 1989; Henry, Cummings, Nelson, & McGhee, 1992; Söndergaard & Theorell, 2004), being a heroin addict in the drug-withdrawal state (Krystal, 1962), having an antisocial personality disorder as a result of pathological socialization.