Visual exploration dynamics are low-dimensional and driven by intrinsic factors

• Published in: Communications biology Vol. 4; no. 1; pp. 1100 - 14
• Main Authors: Zangrossi, Andrea, Cona, Giorgia, Celli, Miriam, Zorzi, Marco, Corbetta, Maurizio
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 17.09.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 631/378/2617/1795; 631/378/2649/1310; Adult; Attention; Biology; Biomedical and Life Sciences; Eye; Eye Movements; Female; Humans; Italy; Life Sciences; Male; Semantics; Students; Visual Perception; Young Adult; Italy
• ISSN: 2399-3642; 2399-3642
• DOI: 10.1038/s42003-021-02608-x

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. Andrea Zangrossi et al. 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.