What Is Fregoli Delusion?
Fregoli delusion is a delusional visuomotor disease belonging to the category of DMS (delusional misidentification syndrome). Human beings have evolved over the other species in recognizing or having the inherent ability to think and cognize, distinguish between objects, places, persons, and things. The capacity to identify people, in particular, is because of the normal neurologic process that aids in the identification and tracking of an individual. In severe psychiatric illness or delusive syndromes like Fregoli delusion, a temporary or maybe even a permanent disruption is caused in this neurologic capacity to identify people correctly. The distinctive errors that creep in these psychiatric diseases, such as schizophrenia, Fregoli delusion, and Capgras delusion, may be due to multiple reasons like a traumatic brain injury or an increase in L-Dopa (Levodopa) hormone.
What Are the Features of Fregoli Delusion?
Fregoli delusion is a rare but complicated syndrome in which the individual suffering from this condition feels or thinks that a single person is replicating multiple personalities or disguises. For the same reason, it is called "delusion of the doubles," meaning that a single person is seen as different people who change their appearance or in several disguises. People and even places, objects, and things can be inaccurately replicated the same way in these cases.
Physicians named this condition after the Italian actor Leopoldo Fregoli who is known for his ability to enact different appearances or roles in his stage acting career. In simple terms, Fregoli delusion is a rare case of delusional misidentification of people, places, or objects.
This delusional belief or hallucination may stem from brain lesions that may alter the individuals' facial perception of others. One more feature of this delusional syndrome is that these patients may often mistake any known or near recognizable face to be someone else altogether, and perception obscurity arises where they mistake that individual to be a persecutor.
The earliest case report of this delusional syndrome is in 1927 by Courbon and Fail, who described a 27-year-old Parisian woman who thought or felt that two actresses (who she used to observe at a theater often) were pursuing or following her in the form of different guises of the people she knew. This lady’s case was the first-ever documented case of this delusional syndrome as she was paranoid about the impersonation she so believed about the actresses. Hence the psychosocial life of these individuals is severely impacted as they hold onto the delusion that the disguised individual is persecuting them and suffer paranoia, stress, and public anxiety.
The clinical features in these patients are mainly;
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Frequent hallucination or delusion episodes.
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Inability to process thoughts correctly.
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Impaired or lack of self-control and awareness.
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Paranoia visual memory loss.
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History of seizures.
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Poor behavior control.
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Epilepsy or epileptogenic episodes.
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Loss of executive brain functions (includes cognitive flexibility, cognitive inhibition control, and attention control) in self-monitoring deficit.
What Is the Pathophysiology or Theories of Delusion?
Dopamine, epinephrine, and norepinephrine are the three major hormones secreted by the adrenal gland of the kidneys. Dopamine and norepinephrine are specifically the two catecholamines or central nervous system neuromodulators secreted in response to psychological or environmental stress. L-Dopa is a precursor to the secretion of these catecholamines or adrenal stress hormones. In Parkinson's disease and in a disorder that is dopamine-related dystonia, L-Dopa is used for a prolonged duration which can increase the catecholamine levels proportionally, increasing stress levels. Hence research of L-Dopa shows that its reduction is linked to fewer delusions in this syndrome, and an increased concentration of the same in patients suffering from Parkinson's disease and dopamine-related dystonia (due to drug therapy) would potentially increase these salient episodes of hallucination or delusion these patients experience.
Documented cases where L-Dopa is a therapeutic agent in treating such diseases like Parkinson's, research indicates that these hallucinatory or delusionary episodes are almost a routine or regular part of the patients' lives in those affected by Fregoli delusion syndrome.
Another major hypothesis for brain lesion causing hallucination is attributed to the theory of traumatic brain injury. According to this theory (by Feinberg et al.), the right frontal lobe and the left temporoparietal lobes may be affected, eliciting a basic deficit in memory and accessory brain functions like attention to detail. Due to the damage in either of these brain lobes, the particular functionality of the brain remains unresponsive, or errors in response regulation and inhibition are seen.
Also, underlying systemic or neurologic diseases or syndromes like schizophrenia, bipolar disorder, and obsessive-compulsive disorder can also be linked to Fregoli delusion syndrome development.
Current research is now focused on identifying damage to the fusiform gyrus or the right temporal lobe of the brain or the auditory P300 component.
How to Manage Fregoli Delusion?
Differential diagnosis of Fregoli's delusion is the Capgras delusion syndrome, wherein the patient feels or perceives a friend or family member to be replaced by an impostor (unlike here wherein a known person is seen as an impostor). However, the patients suffering from these DMS or delusional misidentification syndromes eventually receive similar treatment strategies, mainly by pharmacotherapy with antipsychotic and antidepressant drugs.
Anticonvulsant drugs are also an add-on therapy in patients suffering from convulsive or epileptic episodes. Trifluoperazine, a common antipsychotic drug used to treat schizophrenia, may also be used in a patient suffering from Fregoli delusion if they have additional psychiatric disorders.
Conclusion:
Fregoli syndrome may be quite complicated even though the patient has a normal visuomotor function. However, the cognitive disability in these patients remains a source of concern to those surrounding or the immediate family members or friends. Hence, neurologic intervention should be sought at the earliest, and psychological support should be ensured to the patients to overcome mental health issues and avoid further aggravation of the disease.
