You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is A person falsely perceives that his close friend has been replaced by an exact double. This phenomenon is referred to as: and explain in detail?
Capgras syndrome: false belief that a familiar person or place has been replaced with an exact duplicate. Fregoli delusion, or the delusion of doubles, is a false belief that different people are in fact a single person who changes appearance. Cotard syndrome is a false belief that they are already dead, are putrefying, or have lost their blood or internal organs.