>[!abstract] >The nitrogen in ambient air slightly but measurably impairs human performance compared with a non-anesthetic gas such as helium ([[Winter et al., 1975]]). >[!related] >- **North** (upstream): [[Hyperbaric medicine]] >- **West** (similar): — >- **East** (different): [[Normoxic breathing]] (surface-level gas balance without narcotic effects) >- **South** (downstream): —