In early 2366, Geordi La Forge, Data, and Wesley Crusher worked in a computer access room that was located in the proximity of processor 451. The processors were grouped in arrays of fifty processors each. The room was only accessible by ladder and featured a large desk with LCARS terminals. The walls appeared to be computer processors, implying that the room was located within a computer core.
When the ship was infected with sentient nanites, created and accidentally released by Wesley Crusher, they were located in the computer processors. In order to finish his work with The Egg probe, Doctor Paul Stubbs fired a beam of gamma radiation at the nanites. By doing that he sterilized one of the processors, killing all nanites in the upper core.
When communication was established with the nanites, thanks to the universal translator, Data volunteered to let the creatures enter his neural networks in the computer access room. There, it was agreed that the sentient nanites would be taken to Kavis Alpha IV where they could create their own civilization. (TNG: "Evolution")
A short time later that year, Lieutenant Worf retreated to a computer access room after the death of Marla Aster, feeling guilty and mourning her death. Counselor Deanna Troi followed him into the calm room and comforted him there. (TNG: "The Bonding")