A British man experienced feelings of déjà vu for eight years.
The 23-year-old student told medical experts he had stopped watching TV, listening to the radio, or reading newspapers because he thought he had seen it all before.
Dr Christine Wells, the author of the report, published in the Journal of Medical Case Reports, said: "Rather than simply the unsettling feelings of familiarity which are normally associated with déjà vu, our subject complained that it felt like he was actually retrieving previous experiences from memory, not just finding them familiar.
"Most cases like this occur as a side effect associated with epileptic seizures or dementia.
"However, in this instance it appears as though the episodes of déjà vu could be linked to anxiety causing mistimed neuronal firing in the brain, which causes more déjà vu and in turn brings about more anxiety."