Frégoli syndrome: Causes, signs and symptoms

Frégoli syndrome consists of the belief that extremely strange people in the patient’s environment are impersonated by a known individual.

Within the group of delusional false identification syndromes (SFID) are: subjective doubles syndrome, intermetamorphosis syndrome, capgras syndrome and fregoli syndrome.

For its part, subjective double syndrome is the delusional idea that there are doubles of oneself. Injury to the temporoparietal areas can cause Frégoli syndrome.

Frégoli syndrome is studied in psychiatry. It is also classified as monothematic delusion and delusional misidentification syndrome (DMS). Delusional misidentification syndromes (MDS) are rare neuropsychiatric disorders, their main characteristic being a delusional belief about one’s own identity or a misidentification of people, places or objects.

Like the Capgras illusion, psychiatrists believe it is related to a disturbance in the normal perception of faces.

The syndrome occurs in both sexes, although some studies have reported a higher prevalence among women.

One of the most common causes that trigger Frégoli syndrome is psychosis. Furthermore, delusions are one of the main symptoms of diseases such as schizophrenia and other similar disorders. Therefore, we can define Frégoli syndrome as the delusional belief that different people are actually a single person who disguises themselves.

It should not be confused with Capgras syndrome. Capgras syndrome is the delusional belief that a friend, family member, etc., has been replaced by an imposter twin.

Frégoli syndrome can be related to a brain injury and is often paranoid in nature, in which the delusional person believes that they are being pursued by the person who believes that they are in disguise.

The syndrome has been associated with Alzheimer’s disease in 20 to 30% of patients, grand mal epilepsy, pituitary tumor, closed head trauma, cerebrovascular disease, dementia with Lewy bodies, plaque sclerosis, and Parkinson’s disease. Lithium toxicity has also been described in alcoholic patients and patients with migraine. In typhoid fever and other clinical entities.

Signs and symptoms of Frégoli syndrome:

Hallucinations

Visual memory deficit

Self-control deficit

Self-awareness deficit

Hallucinations

Executive function deficit

Cognitive flexibility deficit

History of seizure activity.

Frégoli syndrome is a double positive illusion where there is excess familiarity with the environment and the familiarity can have four causes:

Impaired self-control: passive acceptance of inaccurate conclusions.

Faulty filtering: Tendency to select important rather than relevant associations.

Mnemonic association of routine thoughts.

Perseverance: unable to find an alternative hypothesis.

Currently, the study of DMS remains controversial as it is often combined with many psychological disorders (i.e. schizophrenia, bipolar disorder, obsessive-compulsive disorder, etc.). Although there is a wealth of information about DMS, there are still many mysteries about the physiological and anatomical details of DMS.

A precise semiological analysis of superior visual anomalies and their corresponding topographic sites may help elucidate the etiology of Fregoli and other misidentification disorders.

Currently, there is no defined treatment for Fregoli syndrome, however, some treatments used for a long time have been shown to have good results. The treatments applied will be pharmacological and behavioral or cognitive-behavioral, among others.