Research on the electrical activity of the brain began already in 1924. From this period is also already known the phenomenon of the so-called alpha block, a reaction of brain waves to increased mental activity. In addition to the alpha-waves the electrical brain activity is also separated in beta, gamma, delta and theta waves. Depending on the location of measurement on the surface of the head, conclusions can be drawn about various mental activities from the activities in the respective frequency bands.

Significance for the emotional intensity: relatively high
Informative value on the kind of emotion: partially
Informative value on the mental workload: high
Effort: complex measurements through electrodes on the scalp surface