Mind prison

Mind prisons were technological devices of the Infinite Empire that were created by the Force-sensitive Rakata species as a means of incarcerating criminals and other beings they considered unsavory. However, these prisons were unusual in that an individual's physical body was not caged, but rather the mind. In part due to losing their connection to the Force, the Infinite Empire collapsed in 25,200 BBY, and the remaining Rakata fled their homeworld of Lehon, where they splintered into the various tribes of the Rakatan Archipelago. A number of tribes took with them the technology of their ancestors, including mind prisons, while other devices became forgotten in the galaxy.

The reality of mind traps were lost in the obscurity of history until 3956 BBY, when the Jedi Revan was commissioned to transport a mind trap—known to him as a mysterious box—from Korriban to Tatooine. In the process, he learned of the existence of mind traps and a small part of their history. At a later date, Elder Ruthic, a descendant of the ancient Rakata, gained the leadership position in the Tulpaa tribe, located in the Rakatan Archipelago, by the use of mind prisons. Being unique due to her growing connection to the Force, Ruthic was able to activate the ancient mind prisons of her people and banish both the tribe's former leaders and her enemies.

Text and facts from the “Mind prison” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.