Neural relay

Neural relays were devices used in the 51st century to let people send "Thought-Mail" by Point-And-Think Technology.

Sometimes, if someone died, their consciousness could still leave an imprint in the neural relay. Using its comms device, the Data Ghost was able, for a short time, to talk to other people, before deteriorating, starting to repeat itself. While usually lasting only a few minutes, Anita mentioned that her Grandfather 'ghosted' for an entire day and kept talking about his shoe-laces.


 * Miss Evangelista's data ghost wanted to talk to Donna, but deteriorated to repetition of "Ice Cream."
 * Proper Dave's, "Hey, who turned out the lights?"
 * Other Dave's "We should go, Doctor!"

Anita was killed by the Vashta Nerada, but had no obvious Data Ghost, as the Vashta Nerada had learned to talk through the neural relay. (DW: Silence in the Library/Forest of the Dead)