This is called the Capgras delusion, and that is a patient, who's otherwise completely normal, has had a head injury, comes out of coma, otherwise completely normal, he looks at his mother and says, "This looks exactly like my mother, this woman, but she's an impostor.
Zove se Capgrasov sumanuti poremećaj, a to je pacijent koji je sasvim normalan, koji je imao ozljedu glave, izašao iz kome, inače sasvim normalan, pogleda svoju majku i kaže, "Ovo izgleda kao moja majka, ova žena, ali ona je uljez --