Capgras Delusion — “My loved one has been replaced”
🧩 Capgras Delusion — “My loved one has been replaced”
Capgras Delusion (pronounced KAP-grahss deh-LOO-zhun) is a delusional misidentification in which a person believes that a close other—such as a parent, spouse/partner, or close friend—has been replaced by an identical-looking impostor.
Even though the patient can clearly recognize the face and voice, the brain fails to produce a feeling of familiarity, leading to the conviction: “They look exactly like her… but I know she isn’t really her.”
This creates a powerful sense of estrangement; some patients become fearful or try to avoid the “impostor.”
🧠 What’s wrong in the brain?
Capgras Delusion is not merely a “wrong belief.” There are measurable distortions in brain processing. Facial processing can be thought of as two partially distinct routes:
| Neural route | Role | When the routes are out of sync |
|---|---|---|
| Fusiform gyrus (temporal lobe) | Identifies faces (who is this?) | Patients can still recognize the face |
| Amygdala pathway | Attaches emotional familiarity/bonding | Patients do not feel the person is familiar |
As a result, the brain experiences “looks like them, but doesn’t feel like them”, and the reasoning system infers: “This must be a double.”
This is captured by the Disconnection Hypothesis (Ellis & Young, 1990): a disconnect between face-recognition systems and emotion systems.
🧬 Brain areas commonly implicated
| Region | Function | If impaired |
|---|---|---|
| Right temporal lobe | Processes identity of familiar faces/voices | Recognizes the person but no felt attachment |
| Limbic system (amygdala) | Generates warmth/familiarity toward intimates | Loss of the “realness”/familiarity signal |
| Prefrontal cortex | Reality-testing and belief evaluation | Poor error-checking, delusion not corrected |
🔬 Key studies & case history
- Original description (1923): French psychiatrists Joseph Capgras & Jean Reboul-Lachaux described a woman convinced that her husband, child, and friends had all been replaced by look-alikes (“l’illusion des sosies” – “illusion of doubles”).
- Ellis & Young (1990): Proposed the disconnection between face recognition (fusiform) and emotional systems (amygdala) as the core mechanism.
- Hirstein & Ramachandran (1997): In a Capgras patient, no galvanic skin response (GSR) to photos of parents (visual route disconnected), but normal emotional response to their voices (auditory route intact). This supports a visual–emotion disconnection.
🧠 Associated conditions
Capgras Delusion often co-occurs with neurological or psychiatric disorders, including:
- Schizophrenia (especially paranoid type)
- Dementias (e.g., Alzheimer’s, Lewy body dementia)
- Right-hemisphere brain lesions or trauma
- Parkinson’s disease (≈ 16% of PD psychosis cases may show Capgras-like misidentifications)
🧬 Psychological perspective
Capgras may arise from emotional–cognitive dissonance: the brain knows (“This is my mother”), but the emotion doesn’t match (“It doesn’t feel like her”).
To reconcile the mismatch, the mind constructs a story: “She must be an impostor.”
🧘♀️ Treatment
There is no single specific cure, but a combined approach is used:
| Approach | Details |
|---|---|
| Medication | Antipsychotics (e.g., risperidone, olanzapine) may reduce delusional intensity |
| Psychotherapy | CBT to gently test beliefs and build alternative explanations |
| Dementia care | Memory/familiarity cues, face recognition aids, consistent routines |
| Family work | Education that this is neurological miswiring, not hatred or willful rejection |
💬 Examples from patients
- “He looks exactly like my husband, but I know he isn’t him.”
- “He walks the same, talks the same, but his eyes feel cold, like a stranger.”
🧠 Links to consciousness theory
Capgras is used to probe the relation between perception (recognizing a face) and recognition-as-familiar (feeling that it’s truly them).
It supports the view that the brain is not a recorder of reality but a constructor of reality—integrating identity with feeling to decide “realness.”
🧠 Quick Summary
| Item | Key point |
|---|---|
| Name | Capgras Delusion |
| Core symptom | Belief that a loved one has been replaced by an identical impostor |
| Key brain areas | Fusiform gyrus, amygdala, prefrontal cortex |
| Mechanism | Disconnection between “knowing” and “feeling familiar” |
| Comorbidities | Schizophrenia, dementias, right-hemisphere injury |
| Treatment | Antipsychotics + CBT; dementia-oriented support |
| Psychological meaning | The brain explains an emotional mismatch by inventing an impostor narrative |
📚 Primary References
- Capgras, J., & Reboul-Lachaux, J. (1923). L’illusion des sosies.
- Ellis, H. D., & Young, A. W. (1990). Accounting for delusional misidentifications. Br J Psychiatry.
- Hirstein, W., & Ramachandran, V. S. (1997). Capgras syndrome… identity and familiarity. Proc. Royal Soc. B.
- Argaud, S., et al. (2019). Neural bases of Capgras syndrome. Schizophrenia Research, 208, 24–31.
- Devinsky, O. (2009). Delusional misidentifications and duplications. Neurology, 72(1), 80–87.
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