Neuropathology was the study of diseases concerning the tissue of the nervous system. On early 21st century Earth this consisted of studying biopsied tissue.
In 2377, while trying to recover the crew of USS Voyager (whose memory engrams had been altered) from the planet Quarra, Commander Chakotay was transferred to Division 6, Neuropathology, under the false accusations of being mentally ill. Unaware of Chakotay's presence, Annika Hansen tried to gain access to neuropathology after she suspected the Quarren of falsifying an outbreak of Dysphoria Syndrome as a cover-up for abduction. (VOY: "Workforce, Part II")