To date, no definitive cause or reason of the disorder has been established. The sources that classify the syndrome as a dissociative disorder or a factitious disorder conflict in their proposed etiologies. As a result, there are a number of theories as to why the syndrome develops.<unk>  was previously classified as a factitious disorder, explaining the symptoms as mimicking of what patients who do not experience psychosis believe is typical of the experience. However, the DSM-IV placed the syndrome under "Dissociative Disorders Not Otherwise Specified". There has been evidence of a strong correlation between approximate answers and amnesia, suggesting that these have an underlying dissociative mechanism. Both<unk> 's syndrome and the broader category of dissociative disorders have been linked to histories of hysteria, psychosis, conversion, multiple personality and possible feigning. Despite this, the condition's etiology remains under question due to associations with established psychiatric disorders, as well as organic states. According to Stern and Whiles (1942),<unk>  is a fundamentally psychotic illness. As evidence, they describe the case of a woman suffering from recurrent mania and a head injury before being submitted to treatment and the report of a schizophrenic male who suffered from alcoholism and had recently been in prison.<unk>  is also sometimes referred to as "prison psychosis", emphasizing its prevalence among prisoners, generating discussion about whether the disorder only appears in this population. In a study of prisoners, Estes and New concluded that escaping an intolerable situation, such as being incarcerated, prompted the syndrome's key symptoms. The study touched on the malingering controversy surrounding the syndrome, as well as the stress component that often precedes the disorder. According to F.A. Whitlock,<unk>  is a hysterical disorder, on par with<unk> 's description of the disorder. Whitlock pointed to the number of cases in which<unk>  was reported in settings of organic brain disease or functional psychosis as evidence of its hysterical foundations. Kraepelin and Bumke also believed the syndrome to be of a hysterical nature. Bumke thought the syndrome hysterical because amnesia for a traumatic emotional event tends to occur in hysteria more than in other disorders. The giving of approximate answers is thought to be produced in hysterical personalities. According to Mayer-Gross and Bleuler,<unk>  occurs mainly in epileptic or schizophrenic patients. Still others claim that an organic condition that could lead to the manifestation of<unk>  symptoms would have to be at an advanced stage in which a diagnosis could be easily given. There have also been reports of trauma and stroke patients with the syndrome. A study investigating the neurological basis of<unk>  described a patient with symptoms of the disorder who had a history of stroke and bifrontal infarcts. They discovered that hyperglutamatergic states, which are caused by both strokes and stress, share a relationship with dissociative symptoms, suggesting a possible organic pathology that can predispose individuals to the syndrome. Wirtz and colleagues (2008) described a patient with<unk>  after a left-hemispheric middle cerebral artery infarct. A neuropsychological examination revealed atypical lateralisation of cognitive functions, leading to the conclusion that the giving of approximate answers might be related to frontal-executive cerebral dysfunction.
Ganser syndrome
Leschke syndrome
Temple–Baraitser syndrome
Schimmelpenning syndrome
Antley–Bixler syndrome
Catel–Manzke syndrome
Eiken syndrome
Gleich's syndrome