Eyetracking is different from the other signals described on this page, since it detects no scalar measurement of the body, but the interaction of a person with the environment. Therefore Eyetracking complements primarily the investigation of other biological signals by capturing the events when the view rests in specific areas of interest (AOI). In addition already the duration of such fixations gives a first clue about the intensity of perception. Many eyetracking devices provide also the additional information of the pupil diameter over time. Under certain conditions this may be a measure of the mental workload (see pupil ).

Significance for the emotional intensity: low
Informative value on the kind of emotion: low
Informative value on the mental workload: low (except pupil)
Effort: to measure using eye trackers