Digit-tracking as a new tactile interface for visual perception analysis

Eye‐tracking is a valuable tool in cognitive science for measuring how visual processing resources are allocated during scene exploration. However, eye-tracking technology is largely confined to laboratory‐based settings, making it difficult to apply to large-scale studies. Here, we introduce a biologically‐inspired solution that involves presenting, on a touch‐sensitive interface, a Gaussian‐blurred image that is locally unblurred by sliding a finger over the display. Thus, the user’s finger movements provide a proxy for their eye movements and attention. We validated the method by showing strong correlations between attention maps obtained using finger-tracking vs. conventional optical eye‐tracking. Using neural networks trained to predict empirically‐derived attention maps, we established that identical high‐level features hierarchically drive explorations with either method. Finally, the diagnostic value of digit‐tracking was tested in autistic and brain‐damaged patients. Rapid yet robust measures afforded by this method open the way to large scale applications in research and clinical settings.