The Collective Unconscious is the central hub from which the player can access all available Mental Worlds. Each doorway is the path to a certain mind/level in Psychonauts. The Collective Unconscious can be accessed via the Brain Tumbler or a PSI-Popper Generator.
Raz can only enter his own mind when he first steps into the Collective Unconscious. The other doors open up once he gains access to them later in the game.
- Levitation jumping off the ring at the right point and floating forwards, it is possible to see a slide such as the ones used for the credits on the main menu, saying "Your Name Here".
- In concept art, the doors were originally supposed to be more personalized for each mental world it led to. This was most likely cut due to time constraints in development.
- Upon entering this area, any mental worlds previously accessed before entering the Lair of the Lungfish will be available, excluding Basic Braining.
- Invisible Walls prevent Raz from walking off the level, but it is possible to Levitation jump over the doors, or to walk off the Brain Tumbler platform. Falling off the level has the same effect as walking off the Brain Tumbler's platform: when entering via the Tumbler, you return to Sasha's Lab, otherwise, you teleport back onto the walkway.
- Raz can still use his real world items in the Collective Unconscious, such as the Dowsing Rod.
- The Collective Unconscious is the only mental area where Raz doesn't wear his protective goggles.
- The game incorrectly displays the location as being "Sasha's Underground Lab" in Raz's journal. While this makes sense if the Collective Unconscious is accessed via the Brain Tumbler, it does not if you've passed the Point of No Return.
- From a technical standpoint the Collective Subconscious is a subarea of the laboratory, as entering a new full on area (e.g. when going from the lake to the main cabin) a loading screen occurs. This loading screen does not occur when Raz uses the Brain Tumbler, meaning it's automatically loaded in when Raz enters the Laboratory.
- Completing all the levels 100% in the game will cause massive text saying "ALL LEVELS 100% COMPLETE! CONGRATULATIONS PSYCHOMASTER!" to float around the area.