Neural depletion was a medical condition in which the entire neural system was drained of electrochemical energy.

In the 19th century, Doctor Beverly Crusher scanned cholera victims in a morgue at the Sisters of Hope Infirmary. She discovered that over half of the victims had experienced neural depletion. This was detemined to be the work of Devidians who had a fondness for Human neural energy. (TNG: "Time's Arrow, Part II")