“That's Long Term Memory. You could get lost in there!”
―Sadness warning Joy
Long Term Memory is a large maze/labyrinth-like area located in Riley's mind in the Disney/Pixar film Inside Out. This place holds every one of Riley's known memories.
It takes the majority of the mind's area and consists of a maze of thousands of banks of stored memories. Since Joy created more memories than the other emotions, most of the orbs are yellow-colored. It communicates with Headquarters, the site of memory production, via numerous vacuum tubes. It is maintained by the Forgetters Paula and Bob, mind workers who remove faded memories and send them in the Memory Dump.
In the film
After Joy and Sadness get vacuumed out of Headquarters, they ended up landing here. In order to get back at Headquarters, the girls must start their journey by first traveling through Long Term Memory. According to Sadness, she says that you can easily get lost in Long Term Memory due to its colossal size and maze-like pathways.
The shelves of Long Term Memory curve and bend in order to evoke the shape of the folds and wrinkles ("gyri" and "sulci") in the brain.