Towards a better description of visual exploration through temporal dynamic of ambient and focal modes

Human eye movements are far from being well described with current indicators. From the dataset provided by the ETRA 2019 challenge, we analyzed saccades and fixations during a free exploration of blank or natural scenes and during visual search. Based on the two modes of exploration, ambient and focal, we used the K coefficient [Krejtz et al. 2016]. We failed to find any differences between tasks but this indicator gives only the dominant mode over the entire recording. The stability of both modes, assesses with the switch frequency and the mode duration allowed to differentiate gaze behavior according to situations. Time course analyses of K coefficient and switch frequency corroborate that the latter is a useful indicator, describing a greater portion of the eye movement recording.