People who experience Capgas syndrome may have an irrational belief that an imposter has replaced someone they know or recognize.

Capgras syndrome (CS) is a psychological condition also known as the delusion of doubles. It is a misidentification syndrome also known as “imposter syndrome” or “Capgras delusion.”

Sometimes, the person experiencing the delusion may believe an animal, object, or even a home is an imposter. CS can affect anyone, but it’s more common in people assigned female at birth. In rare cases, it can also affect children.

People with this syndrome may, for example, accuse a spouse of being an imposter of their actual spouse. This can be upsetting for both the person experiencing the delusion and the person accused of being an imposter.

Learn more about the condition and how best to manage its symptoms.

There are several theories on what causes the syndrome.

The syndrome may occur after structural changes in the brain, such as:

CS can be caused by brain or neurological damage. It may also occur due to another condition affecting the brain, particularly those that affect how the brain perceives or processes information or stores and retrieves memories.

It may occur alongside a combination of physical and cognitive changes.

There isn’t a single cause of CS, and since the condition is so rare, there is still more to learn about how it affects the brain. Here is a look at the potential causes of CS.

Brain injury

The brain is a complex organ and traumatic brain injury (TBI) can lead to changes in brain function. It may affect your mood, balance, and memory, as well as other processes regulated by your brain, such as perceiving what your eyes see or listening and speaking. Some changes can be temporary and others permanent.

When the temporal cortex experiences damage, you can lose the ability to recognize familiar faces visually.

TBI and concussion can lead to CS. This may be due to a disconnect between the temporal cortex and the limbic system, which regulates your emotions.

Prosopagnosia

People can also experience facial blindness, a condition known as prosopagnosia. Some experts suggest that the delusions of Capgas syndrome may occur because those with the condition cannot recognize familiar faces.

However, other researchers disagree that prosopagnosia is a cause of CS, according to a 2019 review of literature. This is mainly because not recognizing a person doesn’t necessarily make one think they are taken over by an imposter.

Neurological conditions

CS may occur with degenerative neurological conditions in which people experience dementia, such as Alzheimer’s disease (AD) and Lewy body dementia. These conditions can affect memory and can alter the person’s sense of reality.

Other neurological disorders associated with CS can include:

Schizophrenia and schizoaffective disorders

Schizophrenia, especially paranoid hallucinatory schizophrenia, can cause episodes of CS. Schizophrenia can also affect your sense of reality and can cause delusions. The same recent 2019 review also found that of 258 people diagnosed with Capgas syndrome, 32% had also been diagnosed with schizophrenia.

CS can also occur in those with schizoaffective disorders. These are mental health disorders in which a person primarily experiences symptoms of schizophrenia in addition to symptoms of mood disorders, such as depression or bipolar disorder.

The researchers also identified other conditions that co-occurred with CS. These conditions included:

The primary symptom of CS is the delusion that familiar people have been replaced by identical doubles or imposters.

Other symptoms can include being aggressive with the person suspected as the imposter. A minority of people with CS may become violent, and research has shown a connection between CS and homicide.

Depending on the underlying cause, such as a neurological disease or schizophrenia, people with CS may experience other symptoms of the contributing condition.

A doctor typically diagnoses this syndrome through a psychiatric evaluation. They may also review your health history and current medications and perform testing to rule out contributing causes such as AD and dementia.

Because CS is a rare condition, its diagnostic criteria are not included in the DSM-5, The Diagnostic and Statistical Manual of Mental Disorders, fifth edition.

CS occurs more frequently in people assigned female at birth than in people assigned male at birth.

Having conditions such as paranoid schizophrenia or neurodegenerative disorders can also put you at a higher risk of developing CS.

Currently, there is no prescribed treatment plan for people with CS. More research on the syndrome is needed. But treatment options may help relieve symptoms.

Treat underlying condition

Treatment aims to address the underlying cause. For instance, if someone with schizophrenia and CS has poor symptom control, treating the schizophrenia with antipsychotic medication can improve the CS.

These treatments may include:

  • medications like cholinesterase inhibitors, which boost neurotransmitters involved in memory and judgment, for dementia and AD
  • antipsychotics and therapy for people with schizophrenia
  • surgery or rehabilitation, if possible, for brain lesions or head trauma

Reality orientation therapy

Reality orientation is a treatment for dementia that involves continuously orienting a person with dementia in the reality of their environment. This includes the time, place, and the people around them. This therapy may help people with dementia better understand their surroundings and feel less anxiety.

For family and caregivers, practitioners recommend that if people undergoing reality orientation therapy express delusions, they should avoid arguing or correcting them. Instead, they suggest bringing the person back to the positive things in their environment to help them stay emotionally connected.

According to a 2017 review, reality orientation can help with cognition and has behavioral benefits for those with dementia.

Behavior therapy

To help people with CS overcome their delusions, mental health therapists may gently discuss the false beliefs while pointing out the evidence in favor of and against them.

In addition, the ABC model in cognitive behavioral therapy is often used to help those affected overcome their delusions. It works by challenging delusional thoughts and beliefs to change how a person responds to them.

Caring for someone with CS can be emotionally demanding, especially if you’re the one they perceive as an imposter. To help someone with CS, here are some strategies to try:

  • Enter their realm of reality when possible. It can help if you try to understand how terrifying it must be.
  • Avoid arguing with them or trying to correct them.
  • Help them feel safe. If you’re unsure what to do, you can ask the person what they need or talk with a healthcare professional.
  • Acknowledge their feelings.
  • If possible, have the “imposter” leave the room. If this is you and you’re the caregiver, let someone else take over until the episode is over.
  • Rely on sound. If you know someone is prone to CS, you can make sure the first way they register your appearance is with sound. Greet them out loud before you see them when possible.

People with CS experience the belief that an imposter has replaced someone they know or recognize.

It can be caused by brain injury, structural changes in the brain, or other conditions such as schizophrenia.

Treating the cause of CS may help improve the symptoms. Behavior therapy may also help the person overcome the mistaken belief.

Q:

What’s the difference between Fregoli syndrome and Capgras syndrome?

Anonymous

A:

Both cause considerable distress for the caregiver as well as the person who has either of these syndromes, but the syndromes are different. In Capgras syndrome, the individual believes that an imposter has taken the place of an important person in their life. In Fregoli syndrome, the person believes that different people are in fact the same person. They believe the person in question is simply changing disguises in order to trick the person with the syndrome.

Timothy J. Legg, PhD, CRNPAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.