Eyetracking-based assessment of affect-related decay of human performance in visual tasks.

Computerized recognition of human emotions enriches the man–machine interaction with a new personal and behavioral aspect. Firstly, because the influence of emotions on the human performance can be objectively assessed and predicted using standardized stimuli, secondly, because an emotion-sensitive computer system can be programmed to react adequately. This paper presents an investigation of emotional influence on the human scanpath. The proposed method assumes that the emotional state of the observer can distract his or her visual attention and can be reliably expressed in parameters of eye movements. We performed visual task experiments in order to record scanpaths from volunteers under auditory stress of controlled intensity. We used a calibrated set of stimuli and controlled the response of volunteers’ central nervous system expressed by the heart rate. For each efficiently stimulated participant, we related the scanpath parameters to the accuracy of solving a given task and to participant’s comment. As a principal result, we obtained a significant change of (1) saccade frequency in 90% and (2) maximum velocity in fixation phase in 80% of participants under stress. These results prove the influence of emotions on visual acuity, feasibility of eyetracking-based assessment of emotional state and motivate further investigations.