The condition is named after the Italian actor Leopold Fregoli who was renowned for his ability to make quick changes of appearance during his stage act.
It was first reported in a paper by Courbon and Fail in 1927. They discussed the case study of a 27-year old woman who believed she was being persecuted by two actors who she often went to see at the theatre. She believed that these people "pursued her closely, taking the form of people she knows or meets".
The Fregoli delusion is classed as a delusional misidentification syndrome, a class of delusional beliefs that involves the misidentification of people, places or objects. Like Capgras delusion, it is thought to be related to a breakdown in normal face recognition processes.
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