Jamais vu is the oposite of déjà vu and occurs when a word or phrase is repeated until it becomes incoherent or meaningless. The phenomenon is casued by the brain becoming fatigued due to semantic satiation.
About 4% of people will have experienced jamais vu (French for ‘never seen‘ as opposed to ‘seen again‘ which is déjà vu) and interestingly the group with whom it is most commonly associated is musicians due to the repetition of words or phrases in songs across multiple or repeated perfoirmances.
Scientists hope that studying jamais vu will help researchers better understand psychiatric disorders like schizophrenia or Capgras delusion, where people believe someone they know very well has been replaced by an impostor.