The worlds quietest place causes human brain to hallucinate

In Minneapolis, Minnesota there is now a room that is so quiet, that the longest time anyone has been able to stay in there is 45 minutes. It's called the "Anechoic Chamber" at Orfield Laboratories, and the owner Steven Orfield says he challenges people to stay in the chamber in the dark. Many people have gone in and most average out to only being able to stay in for 30 minutes. The reason why is because the brain begins to hallucinate after that long of being in dead silence, and you can become disoriented. It's so quiet because of its 3.3 foot thick fiberglass wedges, double walls of steel, and a foot thick wall of concrete. The main purpose of the chamber though is to test the sound quality and volumes of products, such as motor-bikes, washing machines etc. According to Orfield, the chamber filters out 99.99% of all sound, and the only thing that it compares to is the vacuum of space where there is no sound at all. So if you think you're tough enough to handle the dead silence of the Anechoic Chamber, the challenge is always open. 

http://www.dailymail.co.uk/sciencetech/article-2124581/The-worlds-quietest-place-chamber-Orfield-Laboratories.html