Abstract
The transformation of groups of previously nonviolent individuals into repetitive killers of defenceless members of society has been a recurring phenomenon throughout history. This transformation is characterised by a set of symptoms and signs suggesting a common syndrome—Syndrome E. Affected individuals show obsessive ideation, compulsive repetition, rapid desensitisation to violence, diminished affective reactivity, hyperarousal, environmental dependency, group contagion, and failure to adapt to changing stimulus-reinforcement associations. Yet memory, language, planning, and problem-solving skills remain intact. The main risk factors are male sex and age between 15 and 50. A pathophysiological model—“cognitive fracture”—is hypothesised, where hyperaroused orbitofrontal and medial prefrontal cortices tonically inhibit the amygdala and are no longer regulated by visceral and somatic homoeostatic controls ordinarily supplied by subcortical systems. It is proposed that the syndrome is a product of neocortical development rather than the manifestation of a disinhibited primitive brain. Early recognition of symptoms and signs could lead to prevention through education and isolation of affected individuals.
“Repeatedly throughout history, groups of individuals, usually young men, have violently attacked other members of society, often with the approval of, or encouragement from, those in authority. The victims are usually defenceless and are no direct threat to their attackers. Some of the notable manifestations of the phenomenon in this century are the killing of Armenians by Turks in 1915–16, of European Jews during World War II, of Cambodians during the Pol Pot regime in the 1970s, and the ethnic killings in Rwanda in the 1990s. Civil strife, extreme conditions, and ethnic conflicts have often had a role in these events, much as poverty and lack of hygiene lead to outbreaks of infectious disease. Yet these events would not have happened without a distinct transformation in the behaviour of individuals. The uniformity and repeating nature of this transformation suggests a common syndrome affecting individuals for which I propose the term “Syndrome E”. Symptoms and signs Repetitive acts of violence The hallmark of the syndrome is the perpetration of repetitive acts of violence. The individual engages in stereotyped repetition of aggression, characterised by compulsion to spare none of the victims.1,2 Obsessive ideation Individuals are obsessed with a set of beliefs, often directed against a minority group. The combination of repetitive stereotyped acts accompanied by recurring ideation resembles the symptoms and signs of obsessive-compulsive disorder. Metaphors such as “cleansing” are often used to justify violence.2,3 Perseveration Individuals show stereotyped behaviour that perseverates in the face of changing circumstances, even when it is no longer appropriate for the situation and may jeopardise the individual’s interests.3 This behaviour reflects failure to adapt to changing stimulusreinforcement associations.4 Diminished affective reactivity Much of the violence perpetrated by individuals is carried out, not in battlefield frenzy nor in a burst of emotion, but with flat effect. Hyperarousal (Rausch) The repetitive nature of violent acts often invokes a sense of Rausch (elation) according to the number of victims and the magnitude of destruction.5 Intact language, memory, and problem-solving skills Individuals affected by the syndrome usually appear intellectually sound and remain intact in cognitive domains such as language, memory, and the ability to plan and solve problems. Rapid habituation In the early stages of the syndrome, there is rapid habituation to acts of violence. While some report strain with initial homicidal activity, especially toward children and women, most individuals undergo desensitisation within a relatively short time.1 Compartmentalisation Individuals conduct activities calling for seemingly conflicting cognitive states. They may lead a normal family life, while in parallel engaging in killing of families.6 Environmental dependency Behaviour is abnormally dependent on environment and context, which determine the borders of the behavioural compartments described above. Obedience to authority and dependency on group support are examples. Group contagion The group environment is necessary for maintenance of the syndrome and for its propagation. Most individuals in the group respond uniformly to sets of stimuli, and the responses of individuals in the group serves as stimuli for other individuals. Several of the signs and symptoms of Syndrome E are evident in the behaviour of the individual shown in the figure taking aim at a woman and child. The circumstances indicate that the individual had taken part repeatedly in similar acts. The act of killing in front of a photographer is an example of diminution of affective reactivity, but also suggests elation associated with the killing. Compartmentalisation is suggested by the mailing of this and other similar photographs by German soldiers along with accounts of the events to their families at home.3 Risk factors The clearest risk factors are male sex and age of between 15 and 50. There have been attempts to identify other risk factors, including certain personality traits such as authoritarian personality,7 Steiner’s notion of the “sleeper”,8 and obedience to authority.9 However the extensive spread of the syndrome within affected groups casts doubts on the significance of these traits. In a fairly heterogenous group such as the World War II German Police Order Battalions composed of middle-aged men, about 80% became killers of women and children, and only 10%–20% evaded active participation.1 A similar propensity for randomly selected individuals to develop dehumanising behaviour was shown in the Stanford Prison experiment.10 Differential diagnosis Syndrome E is a specific set of symptoms and signs. It is not a general syndrome of human aggression and should not be confused with the behaviour of individuals who carry out repetitive homicidal acts alone. These individuals constitute a very small proportion of the population, and they often have a history of psychopathology. Neither should Syndrome E be confused with the usual manifestations of war or group combat. These conflicts often lead to atrocities, carried out by individuals in the frenzy of battle. Such behaviour, however, lacks most of the features described above and is characterised by inverse symptomatology: emotional reactivity rather than dulling, and incidental, sporadic violence rather than perseveration and systematic repetition.”