Analyzes of individual variability in eye movements

18 October, 2021

Maurizio Corbetta and Andrea Zangrossi, team members of the research project 361/18 - When style matters: do oculomotor fingerprint and brain dynamics explain visual exploration and memory strategies?, analyze individual variability in eye movements when healthy participants view images of natural scenes. Their results suggest that eye movement patterns can be summarized by three principle components, and depend more on subjects' intrinsic characteristics than the visual contents of the scene. To know more, check the paper “Visual exploration dynamics are low-dimensional and driven by intrinsic factors” published in Communications Biology.

“When looking at visual images, the eyes move to the most salient and behaviourally relevant objects. Saliency and semantic information significantly explain where people look. Less is known about the spatiotemporal properties of eye movements (i.e., how people look). We show that three latent variables explain 60% of eye movement dynamics of more than a hundred observers looking at hundreds of different natural images. The first component explaining 30% of variability loads on fixation duration, and it does not relate to image saliency or semantics; it approximates a power-law distribution of gaze steps, an intrinsic dynamic measure, and identifies observers with two viewing styles: static and dynamic. Notably, these viewing styles were also identified when observers look at a blank screen. These results support the importance of endogenous processes such as intrinsic dynamics to explain eye movement spatiotemporal properties.”