People with this disorder believe that every new person that they meet is either impersonating or wearing a mask that mimics the people that they are closest to – no matter what the person looks or acts like. They are irrationally convinced that these strangers have taken the place of their loved ones by wearing cunning disguises that mimic their faces, which, of course, disrupts any normal social interaction that this person could have.
The associative nodes in the brain are the main biological factor associated with this disorder. They link all information about other people with a particular familiar face to the patient, meaning that for any face that is similar to a recognizable face, the patient will recall that face as the familiar person.
Fregoli Disorder is classified as both a monothematic delusion, since it is only focused on one delusional topic (the assumption that strangers are impersonating loved ones), as a delusional misidentification syndrome, which is a class of delusional beliefs that involves the misidentification of people, places, or things.
The main symptoms of Fregoli Disorder are delusions, deficits in executive functioning, visual memory deficits, epileptogenic activity, deficits in self-monitoring and self-awareness, and hallucinations.
There are several known causes of this disorder:
- Levodopa Treatment: A treatment used in cases of Parkinson’s disease and dopamine-responsive dystonia, levodopa treatment has been proven to lead to visual hallucinations and delusions in some cases, with delusions often being more prominent than hallucinations. After prolonged use of this form of treatment, the delusions become the center of the patient’s attention. These delusions can include those that characterize Fregoli Disorder.
- Traumatic Brain Injury: Injuries to either the right frontal or temporo-parietal areas of the brain can cause significant deficits in executive and memory functions, which can, in turn, result in Fregoli Disorder. Patients with brain injury to these areas often have trouble when it comes to detailed attention tasks, and the ability to retrieve memories is significantly impaired, both of which are symptoms of this disorder.
- Fusiform Gyrus: Lesions on this area of the brain can contribute to delusional misidentification syndromes, especially since there is a face-specific region close to the anterior fusiform gyrus – if this portion is damaged, then there is a high probability that the patient will have a lot of trouble associating names and faces, and there is a high correlation between this and Fergoli Disorder.
Pharmacotherapy is the main form of treatment for this disorder: antipsychotic drugs are often prescribed, but anticonvulsants and antidepressants can also be used to treat symptoms.
The first case was reported in a 1927 paper published by P. Courbon and G. Fail, who described the case of a 27 year old woman that was living in London. She believed that she was being persecuted by two actors that she often saw at the theater, since she saw them taking the form of people that she knew or had met, and that they were pursuing her closely.
Interestingly enough, the disorder is named after an actor that was renowned for his ability to make quick costume changes during his stage acts, an Italian by the name of Leopoldo Fregoli.