The exact cause of Capgras syndrome, or imposter syndrome, is unknown. It is commonly associated with Alzheimer’s or dementia
Capgras syndrome, or imposter syndrome, is a complex psychological condition characterized by an irrational belief about another person’s identity. A person with the syndrome believes that a person they know has been replaced by an imposter or double.
Capgras syndrome is often associated with other psychiatric disorders such as schizophrenia (especially the paranoid type), mood disorders, or neurological disorders.
There are four conditions seen in a patient with Capgras syndrome:
- The patient affirms the resemblance of the double to the misidentified person.
- No identity is attributed to the double.
- The double is an imposter, replacing and pretending to be the original.
- The original has disappeared, with their absence remaining unquestioned.
What part of the brain causes Capgras syndrome?
The exact cause of Capgras syndrome is unknown, but several theories have been put forward.
The Capgras delusion is more common in individuals diagnosed with paranoid schizophrenia and organic brain disorders, such as dementia, and neurodegenerative disorders, such as Alzheimer's disease and epilepsy.
Some believe it is caused by a problem within the brain, such as atrophy, lesions, or cerebral dysfunction, specifically the combination of:
- frontal lobe damage (causing problems with familiarity) and
- right hemisphere damage (causing problems with visual recognition).
Others believe that it’s a combination of physical and cognitive changes, which may lead to:
- loss of connection between the parts of the brain that process visual information and
- loss of limbic system control in which feelings of disconnectedness contribute to the problem.
What are the signs and symptoms of Capgras syndrome?
A person with Capgras syndrome feels that a person close to them has been replaced by an imposter that looks exactly the same as the original. The impostor is always a person with whom the patient is familiar and not a stranger. In chronic stages, the condition may extend to animals or objects.
Clinical features include:
- Impostor delusion
- Anxiety
- Depression
- Hallucination
- Cognitive impairment
- Ataxic gait
- Confusion
- Irritability
- Loss of trust
- Insomnia
- Delusion of persecution
- Social withdrawal
How is Capgras syndrome diagnosed?
As Capgras syndrome is a rare psychiatric condition, there is no established diagnostic criteria to rule out this type of delusional disorder.
The condition is mainly diagnosed with the psychiatric evaluation of the patient who shows symptoms of having delusional belief of an impostor.
How is Capgras syndrome treated?
While there are no standard treatment methods for patients with Capgras syndrome, treatment options that may help reduce and relieve the symptoms include the following:
- Antipsychotics, which may help treat schizophrenia and control episodes of Capgras syndrome
- Medications that inhibit the enzyme acetylcholinesterase and increase the level of ACh in the brain, which help boost memory and judgment in elderly people with Alzheimer’s disease and dementia
- Behavior therapy for managing symptoms of delusion
- Reality orientation therapy
- Creating a therapeutic, positive, and welcoming environment where the person affected by the syndrome feels safe
- Reducing the delusional stimuli, which helps reduce anxiety