A psychoscan is a type of medical scan specifically for detecting and diagnosing mental illnesses or other conditions. A psychotricorder could be used for such scans in field conditions. (TOS episode: "Wolf in the Fold")

Dr. Krisp ran a psycho-probe on Jay Nordyke, an investigator who inspected the Mila-Xa asteroid in the Delta system, then was unable to remember part of his visit. Krisp thought his memory loss might be caused by severe shock or brain tampering, and recommended the probe. Nordyke agreed, and during the probe he was able to recall traumatic incidents during the mission. (TOS comic: "The Haunted Asteroid")

Starfleet Regulation 73-C, Subsection A, required all Starfleet personnel to undergo a routine psychological scan at least once a year, or whenever deemed necessary by a physician. Dr. Leonard McCoy pressed Admiral James T. Kirk to undergo a psychoscan in 2284, to determine a reason for his recurring dreams about the characters and events from the book Strangers from the Sky. Later it was determined that Captain Spock displayed identical readings from his own psychoscan. (TOS novel: Strangers from the Sky)