The where, what and when of gaze allocation in the lab and the natural environment

Abstract

How do people distribute their visual attention in the natural environment? We and our colleagues have usually addressed this question by showing pictures, photographs or videos of natural scenes under controlled conditions and recording participants' eye movements as they view them. In the present study, we investigated whether people distribute their gaze in the same way when they are immersed and moving in the world compared to when they view video clips taken from the perspective of a walker. Participants wore a mobile eye tracker while walking to buy a coffee, a trip that required a short walk outdoors through the university campus. They subsequently watched first-person videos of the walk in the lab. Our results focused on where people directed their eyes and their head, what objects were gazed at and when attention-grabbing items were selected. Eye movements were more centralised in the real world, and locations around the horizon were selected with head movements. Other pedestrians, the path, and objects in the distance were looked at often in both the lab and the real world. However, there were some subtle differences in how and when these items were selected. For example, pedestrians close to the walker were fixated more often when viewed on video than in the real world. These results provide a crucial test of the relationship between real behaviour and eye movements measured in the lab.

Are fixations in static natural scenes a useful predictor of attention in the real world?

“…The empirical, real-world distribution in Figure 4 mirrors the more general pattern demonstrated throughout the walk and reported in Foulsham et al (2011), with gaze being more frequent along the vertical midline. However, in that study we did not investigate the specific locations in the scene that were fixated, and we used a contiguous video presentation meaning that the results might not extend to static scene viewing.…”

“…Participants walking in the real world spent more time paying attention to the path, and less time looking at pedestrians who were close to the observer, but there were some objects and pedestrians that were fixated equally in both walking and watching. Thus, unlike the results from t 'Hart et al (2009), Foulsham et al (2011 placed an emphasis on the differences between real-world gaze and fixations on video. However, because we looked at aggregate gaze times on objects of interest and not the pixel-based fixation coordinates at particular times, and because we did not test the -7-commonly-used static scene presentation in the lab, it is not straightforward to apply the results to attention in scene viewing.…”

“…Measurements of natural gaze come from Foulsham et al, (2011), where they are described in full. In brief, fourteen participants (nine females) were recorded during a self-guided walk across the UBC campus in Vancouver, Canada, walking outdoors in a mostly pedestrianized area.…”

“…We describe results from a new study, comparing participants looking at static images to those who observed the same scenes while walking in the real world in Foulsham et al (2011). There is a growing amount of research documenting gaze in active, natural tasks including walking, driving, sports and carrying out sequential everyday routines (Land et al, 1999;Land, 2009;Hayhoe & Ballard, 2005).…”

“…In Foulsham et al (2011), we also replayed videos from a head-mounted eyetracker to participants in the lab. The mobile data came from participants walking unconstrained in an outdoor, campus environment.…”