Doctors and scientists aren't really sure why they happen, but they have a few theories. One theory is that your brain misunderstands the sensation of your muscles relaxing as you drift off to sleep. It's normal for the muscles to relax, but the brain gets confused, and, for a minute, thinks you're falling. In response, the brain causes your muscles to tense up so you catch yourself before you fall down.
The former Beatle Paul McCartney has married American heiress Nancy Shevell at Marylebone register office in London. The couple waved to crowds packed behind security barries after they made the short drive from Sir Paul's north London home to the venue.
*Paul has made millions of dollars from sold out tours, concerts, album sales right from his days as a member of the defunct music group The Beatles. Paul McCartney net worth is estimated at $900 million, this estimation is together with his wife net worth Nancy Shevell.