Bridge control relays, or bridge access relays, were components of holodeck control panels which allowed one to gain access to holodeck systems from the bridge of the ship.
In 2374, in an attempt to deactivate the neural interfaces with which the crew of the USS Voyager had been outfitted by the Hirogen, Seven of Nine accessed the bridge control relays in the holodeck, allowing The Doctor to deactivate Captain Janeway's interface from sickbay. (VOY: "The Killing Game")