Do you experience deja vu? It happens to me quite frequently, but rather than scare me or stress me out, I find it intriguing. 
Terrifying time loop: The man trapped in constant deja vu
Scientists believe the extraordinary case of a 23-year-old British man with "constant deja vu" may have been triggered by anxiety. It is the first time such a link has been made. But what is deja vu - and do we really know what causes it?
Most of us know the feeling - the fleeting sensation that you have been somewhere or done something before, when common sense tells you that is not possible. The term deja vu translates literally from French as "already seen". According to research, about two thirds of us experience at least one deja vu in our lifetime, yet very little is known about what causes it.
The group of scientists from the UK, France and Canada who studied the strange case of the man with "chronic deja vu" think one possible cause of the phenomenon could be anxiety. The man's condition was so persistent he avoided watching television, listening to the radio and reading newspapers because he felt he had "encountered it all before".
Dr Chris Moulin, a cognitive neuropsychologist at the University of Bourgogne who worked on the study, says the man had a history of depression and anxiety, and had once taken the drug LSD whilst at university, but was otherwise completely healthy. "This man was striking because he was young, otherwise aware, but completely traumatised by this constant sensation that his mind was playing tricks," he says. For minutes, and sometimes even longer, the patient would feel that he was reliving experiences.
He likened the "frightening" episodes to being in the psychological thriller film Donnie Darko. "There was one instance where he went to get a haircut. As he walked in, he got a feeling of deja vu. Then he had deja vu of the deja vu. He couldn't think of anything else," says Dr Moulin. For eight years, the man felt "trapped in a time loop". The more distressed he became by the experience, the worse it seemed to get.
People first experience deja vu at the age of about six or seven, and it happens most often between the ages of 15 and 25, before tailing off as people get older, according to research by Professor Alan Brown at South Methodist University in Dallas.
There are several other theories about what causes the sensation. Dr Akira O'Connor, a psychologist from the University of St Andrews, believes that in most cases it is a momentary "misfiring" of neurons in the brain which creates false connections.
"One idea is that deja vu is a sort of 'brain twitch'. Just as we get muscle spasms, or eye twitches, it could be that the bit of your brain which sends signals to do with familiarity and memory is firing out of turn," he says. He says this fits with evidence that deja vu is more frequently experienced by people with epilepsy and dementia.
http://www.bbc.com/news/uk-30927102
Terrifying time loop: The man trapped in constant deja vu
Scientists believe the extraordinary case of a 23-year-old British man with "constant deja vu" may have been triggered by anxiety. It is the first time such a link has been made. But what is deja vu - and do we really know what causes it?
Most of us know the feeling - the fleeting sensation that you have been somewhere or done something before, when common sense tells you that is not possible. The term deja vu translates literally from French as "already seen". According to research, about two thirds of us experience at least one deja vu in our lifetime, yet very little is known about what causes it.
The group of scientists from the UK, France and Canada who studied the strange case of the man with "chronic deja vu" think one possible cause of the phenomenon could be anxiety. The man's condition was so persistent he avoided watching television, listening to the radio and reading newspapers because he felt he had "encountered it all before".
Dr Chris Moulin, a cognitive neuropsychologist at the University of Bourgogne who worked on the study, says the man had a history of depression and anxiety, and had once taken the drug LSD whilst at university, but was otherwise completely healthy. "This man was striking because he was young, otherwise aware, but completely traumatised by this constant sensation that his mind was playing tricks," he says. For minutes, and sometimes even longer, the patient would feel that he was reliving experiences.
He likened the "frightening" episodes to being in the psychological thriller film Donnie Darko. "There was one instance where he went to get a haircut. As he walked in, he got a feeling of deja vu. Then he had deja vu of the deja vu. He couldn't think of anything else," says Dr Moulin. For eight years, the man felt "trapped in a time loop". The more distressed he became by the experience, the worse it seemed to get.
People first experience deja vu at the age of about six or seven, and it happens most often between the ages of 15 and 25, before tailing off as people get older, according to research by Professor Alan Brown at South Methodist University in Dallas.
There are several other theories about what causes the sensation. Dr Akira O'Connor, a psychologist from the University of St Andrews, believes that in most cases it is a momentary "misfiring" of neurons in the brain which creates false connections.
"One idea is that deja vu is a sort of 'brain twitch'. Just as we get muscle spasms, or eye twitches, it could be that the bit of your brain which sends signals to do with familiarity and memory is firing out of turn," he says. He says this fits with evidence that deja vu is more frequently experienced by people with epilepsy and dementia.
http://www.bbc.com/news/uk-30927102
