Description

An electroencephlogram, or EEG, is a test that detects abnormalities in your brain waves, or in the electrical activity of your brain. The device works by placing electrodes consisting of small metal discs with thin wires are pasted onto the participant's scalp. The electrodes detect tiny electrical charges that result from the activity in brain cells. The charges are amplified and appear as a graph on a computer screen, or as a recording that may be printed out on paper. 
In Human Factors, EEGs are used typically to measure performance with respect to mental fatigue, mental workload, mental effort, visual fatigue, emotion, and stress.Many studies in human factors focus on evaluating an individual’s mental states while operating a vehicle, however there are plenty of other practical applications for using an EEG.
Outside of Human Factors, The EEG can be used used to evaluate several types of brain disorders, diagnose other disorders that influence brain activity, determine the overall electrical activity of the brain, and to monitor blood flow in the brain during surgical procedures.