Submission 108
The Statistics of Natural Gaze Behavior in Active Everyday Tasks
SymposiumTalk-05
Presented by: Alexander Goettker
Many studies trying to understand natural gaze movements use the presentation of naturalistic images on a computer screen with restrained head movements. However, in the natural world, we often use a combination of eye and head movements to shift our gaze. Here we employ state-of-the-art mobile recording techniques to describe the statistics of eye and head movements during active, everyday tasks and compare them to screen-based tasks. The same group of participants completed three different tasks: (1) free-viewing of naturalistic images on a screen, (2) block building, and (3) copying of an image. Our results provide three key insights. First, an automated movement labeling pipeline allowed us to describe the statistics of natural eye and head movements in active real-world tasks. Notably, a substantial proportion of gaze fixations (around 30%) happen while the head is moving and the gaze is stabilized via the vestibular-ocular reflex. Second, we observed novel gaze strategies that are not observed in the screen-based task. For example, there seems to be a strategic combination of blinks and large head movements. Third, we leveraged reliable individual differences in average gaze statistics (e.g., saccade rate) across tasks to compute the possible level of generalization from the screen to the real world. There were only limited relationships between the screen-based task and the natural tasks, indicating that the passive free-viewing screen-based task is not a good descriptor of active real-world gaze behavior. Together, our results highlight the need to study natural behavior in vivo.