I feel like “Mind Palace” has been mentioned before. I can’t remember where though.

The method of loci (loci being Latin for “places”) is a method of memory enhancement which uses visualizations with the use of spatial memory, familiar information about one’s environment, to quickly and efficiently recall information. The method of loci is also known as the memory journey, memory palace, or mind palace technique. This method is a mnemonic device adopted in ancient Roman and Greek rhetorical treatises (in the anonymous Rhetorica ad Herennium, Cicero’s De Oratore, and Quintilian’s Institutio Oratoria). Many memory contest champions claim to use this technique to recall faces, digits, and lists of words. These champions’ successes have little to do with brain structure or intelligence, but more to do with using spatial memory and the use of the method of loci.

Fictional portrayals of the method of loci extend as far back as ancient Greek myths. The method of loci also features prominently in the BBC series Sherlock, in which the titular main character uses a “mind palace” to store information. In the original Arthur Conan Doyle stories, Sherlock Holmes referred to his brain as an attic.