At the end of the procedure a flashing light may be placed nearby to see if this affects your brain activity. Sleep EEG or sleep-deprived EEG. A sleep EEG is carried out while you're asleep. It may be used if a routine EEG doesn't give enough information, or to test for sleep disorders.
This is all I could find on years...Prometheus was originally intended as a direct prequel to the 1979 science fiction horror film Alien, set approximately 30 years before the events depicted in the film. Alien supposedly takes place around 2122. Prometheus had a date of 2093 according to the intro.
Alien (movie series and creative franchise) The first film in chronological order of the Alien/Predator franchise is the film Predator. That film takes place in the late 1980s and it begins the entire series. In fact, all of the Predator films take place in modern times, although obviously in a fictional universe. Chronologically Alien vs. Predator shows the first Xenomorph, although this film was released nearly 25 years after the Alien franchise began.