Neural monitor
From Memory Alpha, the free Star Trek reference.
A neural monitor is a medical device that monitors nervous system activity.
In 2377, the con artist Gar offered to sell Administrator Chellick of Dinaali Hospital Ship 4-2 the Doctor's mobile emitter, which he had stolen from the USS Voyager. Chellick at first took it for a neural monitor, and replied that they had no need for more. (VOY: "Critical Care")
