Seminar: 10/19 - Paul Bays, University College London
11:00 to 12:30 PM at: 5101 Tolman Hall
Visual working memory in actionVisual memory, attention and eye movements usually work in harmony to provide us with a seamless representation of the environment in which to plan our actions. An influential model of working memory capacity proposes a fixed number of independent memory 'slots' each representing a single visual object. I will show that storage in visual working memory is -- contrary to this conventional model -- a highly flexible process, in which limited resources are dynamically allocated towards behaviourally-important objects in the environment. Working memory is thought to support exploration of the visual world via a mechanism that inhibits returning gaze to previously-examined locations. However, analysis of eye movement patterns in naturalistic visual scenes reveals a very high frequency of gaze shifts back to the previous fixation, apparently contradicting this hypothesis. I will present a novel analysis of natural gaze data that decomposes saccade selection into three components: the attentional priority observers assign to different regions of a scene, their systematic bias towards certain amplitudes and directions of eye movement, and the effect of gaze history. The results demonstrate a vital role of memory in inhibiting refixation in natural vision.