Guest Lecture of Paul Bays

Guest Lecture of Paul Bays

from the Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London


Date: 12 December 2012

Topic: Visual Working Memory in Action

Abstract:
Visual 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. Contrary to this conventional model, I will show that storage in visual working memory is a highly flexible process, in which limited resources are dynamically allocated towards behaviourally-important objects in the environment. A possible biological basis for this resource can be found in neural population coding, and I will present evidence that observers allocate neural activity in a near-optimal fashion under these constraints. 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 demonstrates a vital role of memory in inhibiting refixation in natural vision.