2. Capgras Delusion
The Capgras Delusion is a rare but striking psychological disorder in which someone believes a close friend or family member has been replaced by an identical impostor. In one famous case, a woman insisted her husband was a double, despite recognizing his appearance. Neurologists believe this may result from a disconnect between facial recognition and emotional response—the face is familiar, but the emotional connection is missing. Research into delusional misidentification syndromes continues to shed light on this unsettling break between perception and belief.