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.
Ridley Scott: 'Alien: Covenant' Is First of 3 Films Before Linking Up With Original 'Alien'. The director revealed details of the 'Alien' origin stories as he begins pre-production on the followup to 'Prometheus' in Australia. Ridley Scott confirmed that he is planning another two Prometheus sequels to follow Alien: Covenant before the Prometheus storyline meets up with the original 1979 Alien.