Philip K Dick would have loved this kind of stuff:
Capgras syndrome – in which the patient believes their friends and relatives have been replaced by impersonators – was first described in 1923 by the French psychiatrist J.M.J. Capgras in a paper with J. Reboul-Lachaux.
Now Alireza Nejad and Khatereh Toofani at the Beheshti Hospital in Iran have reported an extremely rare variant of Capgras syndrome in which a 55-year-old woman with epilepsy believes her possessions have all been replaced by substitute objects that don’t belong to her. When she buys something new, she immediately feels that it has been replaced.
More on this, and other research news, at the BPS Research Digest (written by Christian Jarret)