For example, unsubstantiated or unverifiable claims of being followed by the FBI in unmarked cars and watched via security cameras would be classified as a non-bizarre delusion; while it would be unlikely for the average person to experience such a predicament, it is possible, and therefore understood by those around them. Mood-congruent delusions
These correspond to a persons emotions within a given timeframe, especially during an episode of mania or depression. For example, someone with this type of delusion may believe with certainty that they will win $1 million at the casino on a specific night, despite lacking any way to see the future or influence the probability of such an event. Similarly, someone in a depressive state may feel certain that their mother will get hit by lightning the next day, again in spite of having no means of predicting or controlling future events. Mood-neutral delusions
These are unaffected by mood, and can be bizarre or non-bizarre; the formal definition provided by Mental Health Daily is "a false belief that isnt directly related to the persons emotional state." An example would be a person who is convinced that somebody has switched bodies with their neighbor, the belief persisting irrespective of changes in emotional status. Biopsychosocial effects
As with many psychiatric disorders, shared delusional disorder can negatively impact the psychological and social aspects of a persons wellbeing. Unresolved stress resulting from a delusional disorder will eventually contribute to or increase the risk of other negative health outcomes, such as cardiovascular disease, diabetes, obesity, immunological problems, and others.
Doyle believe folie à plusieurs to have been at least a partial factor in the murder of Bridget Cleary. In 1895, Michael Cleary convinced several friends and relatives that his wife, Bridget Cleary, was a changeling who had been replaced by a fairy. They assisted him in physically abusing her to "cast the fairies" out, before he ultimately burned her to death shortly afterwards. Christine and Léa Papin were two French sisters who, as live-in maids, were convicted of murdering their employers wife and daughter in Le Mans, France on February 2, 1933. Born in Yemen in 1963 to Barbados immigrants, June and Jennifer Gibbons were known as "the Silent Twins" for speaking solely to each other in an idioglossia derived from an idiosyncratic, sped-up Bajan Creole dialect that qualified as an example of cryptophasia. The inseparable twins had a longstanding agreement that, if one died, the other must begin to speak and live a normal life, and it was during their 11-year admission to Broadmoor Hospital — where the twins had been indefinitely placed following a series of crimes (e.g. vandalism, petty theft and arson) in 1981 — that they began to believe that it was necessary for one of them to die. Jennifer agreed it should be her, and when the twins were transferred from Broadmoor to the more open Caswell Clinic in Bridgend, Wales in 1993, Jennifer could not be roused upon arrival. She was taken to the hospital where she died soon after of acute myocarditis, or inflammation of the heart.