Jayden was the name given to Lieutenant Commander Data by Gia, a young girl from the planet Barkon IV, when he arrived in her village suffering from amnesia in 2370.
It was deduced that "Jayden" was an "ice-man" from the northern Vellorian Mountains by the town scientist and healer, Talur. Data was in fact on a mission to Barkon IV to retrieve the radioactive remains of a probe that had crashed on the planet's surface.
Jayden was "killed" by a spear through his abdomen when attacked by an angry mob of villagers, blaming him for bringing them a plague. The "plague" was, in actuality, radiation sickness caused by the metal fragments in his possession.
He was buried in a marked grave beneath the town square after it was realized he introduced a cure into the water supply just before his demise. His body was transported back to the USS Enterprise-D, unbeknownst to the villagers. (TNG: "Thine Own Self")
Jayden was, like Data, played by Brent Spiner.
A cut line from the episode would have revealed that "Jayden" was a handsome nobleman in a Barkonian story who was transformed into a frog by a demon's spell. (Star Trek: The Next Generation Companion, 2nd ed., p. 284)