Séminaire IPI : « Predicting artificial visual field losses: a gaze-based inference study »
25 janvier 2019 @ 14 h 00 min - 15 h 00 min
The next IPI seminar will held
on Friday, the 25th of January (2pm-3pm).
The room (at Polytech) will be D005.
The speaker will be Erwan David who is PhD student in the IPI team.
Title: Predicting artificial visual field losses: a gaze-based inference study
Visual field defects are a world-wide concern, the proportion of the population experiencing vision loss is ever increasing. Macular degeneration and glaucoma are among the four leading causes of permanent vision loss. Identifying visual field losses from gaze alone could prove crucial in the future for screening tests. Gaze movements and scanpaths contain a wealth of information (Coutrot, Hsiao, & Chan, 2018). Gaze features related to saccades and fixations have demonstrated their usefulness in the identification of mental states, cognitive processes and neuropathologies (Itti, 2015).
54 participants took part in a free-viewing task of visual scenes while experiencing artificial scotomas (central and peripheral) of varying diameters in a gaze-contingent paradigm (Duchowski, Cournia, & Murphy, 2004). We study the importance of a set of gaze features as predictors to best differentiate between scotoma conditions. We first report effect sizes with Linear Mixed Models (LMMs), then show redundancies in variance with a correlation and a factorial analyses. We end by implementing Hidden Markov Models (HMMs) and Recurrent Neural Networks (RNNs) as classifiers in order to measure predictive usefulness of gaze features. We demonstrate that saccade relative angle, amplitude and peak velocity are the best gaze features to distinguish between artificial scotomas of different types and diameters.