Spatial statistics for gaze patterns in scene viewing: Effects of repeated viewing

This work was funded by Deutsche Forschungsgemeinschaft (DFG, German Research Foundation, grant EN 471/13–1 to R.E.) and the Collaborative Research Centre SFB 1294, project number B05 and by Bundesministerium für Bildung und Forschung (BMBF) via Bernstein Center for Computational Neuroscience Berlin (Project B3, Förderkennzeichen 01GQ1001F to R.E. & F.A.W.). Simon Barthelme was supported by an ANR grant (GenGP, ANR-16-CE23-0008).International audienceScene viewing is used to study attentional selection in complex but still controlled environments. One of the main observations on eye movements during scene viewing is the inhomogeneous distribution of fixation locations: While some parts of an image are fixated by almost all observers and are inspected repeatedly by the same observer, other image parts remain unfixated by observers even after long exploration intervals. Here, we apply spatial point process methods to investigate the relationship between pairs of fixations. More precisely, we use the pair correlation function, a powerful statistical tool, to evaluate dependencies between fixation locations along individual scanpaths. We demonstrate that aggregation of fixation locations within 4° is stronger than expected from chance. Furthermore, the pair correlation function reveals stronger aggregation of fixations when the same image is presented a second time. We use simulations of a dynamical model to show that a narrower spatial attentional span may explain differences in pair correlations between the first and the second inspection of the same image