Abstract
Research has shown that eye movements are beneficial for the perception of scenes. Specifically, we have previously shown that when eye movements are disallowed during the encoding of a scene in a memory experiment, recognition accuracy falls to chance at test. This suggests that eye movements during the first viewing of a scene, used to visually explore and encode the scene, are critical for accurate subsequent memory. Here we probe whether it is possible to enhance memory by encouraging people to explore scenes more thoroughly by prompting them to make more eye movements during scene viewing. Seven participants viewed photographs of real-world scenes, followed by a new-old memory task. They were either allowed to look around the scene as they pleased (LOOK condition), or were instructed to make more eye movements throughout the scene (EXPLORE condition). An index of exploration behaviour was calculated as the root-mean-square-distance (RMSD) from initial fixation, weighted by fixation duration. Participants were able to follow instructions, in that their RMSD was significantly higher in the EXPLORE condition (5 degrees) than the LOOK condition (4.4 degrees, p < 0.05). However, recognition accuracy (hit rate) did not differ between conditions, meaning that the extra exploration did not have an influence on memory. These results, along with the results from our previous study, demonstrate that eye movements are necessary for proper encoding and thus accurate subsequent memory. However, once overt attention is already deployed, greater exploration within the same timeframe does not increase encoding efficiency. Therefore, the link between memory and scene exploration is likely a reflection of overt attention during encoding.
Meeting abstract presented at VSS 2017