While electroencephalography (EEG) has been used for decades to measure voltage fluctuations in different parts of the brain to graph a person’s neural patterns, determine brain injuries, and monitor the effects of sedatives and anesthesia, “there are really no set standards within the EEG community of how you confirm the equipment is working the way you really think it is,” says David Hairston, a neuroscientist at the Army Research Lab’s Human Research and Engineering Directorate in Maryland.

EEG requires having a biological voltage fluctuation, and a lot of electrically unwanted noise is generated when the EEG is in use. The neurons in the brain produce tiny electrical voltages that the EEG detects as patterns and electrical interference can overlay those patterns.

So the Army is building a molded “phantom head” containing recorded brain waves from a human that are played back through wires inside the head to sensors on the outside. When the phantom head is hooked up to an EEG machine, aberrations to the wave patterns can be detected and electrical interferences can be accounted for and subtracted during testing so that a pure EEG reading of the test subject can be made, he explained.