Attention: Work(ing Memory) in Progress
Susanne Ferber
University of Toronto

How do we keep track of oncoming traffic while checking our rear-view mirrors? Selecting and sustaining a percept after it has been removed from view involves attentional and visual working memory (VWM) processes that enable us to hold in our mind's eye the contents of our visual awareness and to decide which inputs will continue forward for further processing. VWM is a temporary storage system for visual input in which information is kept safe for a few seconds across eye movements and other intervening events. From crossing the street to calculating the tip at a restaurant, our success with countless basic and higher-order tasks depends on our ability to mentally represent external events, so they can be integrated with both the attentional system and long-term knowledge to determine our decisions and actions. The bandwidth of information available to our senses is almost infinite, yet the bandwidth of information our brain is able to process in a meaningful way is severely limited. Indeed, most theories of VWM posit a capacity limit of less than four items. This is in stark contrast to our subjective experience of the present moment and our recollection of events from memory. Normally the VWM system works well, but it may be disrupted in healthy individuals when it is overloaded, may show different characteristics in populations with neural developmental disorders, and may fail altogether after brain damage. Despite our growing understanding of the neural and cognitive processing limitations of VWM, we know little about how VWM ultimately affects visually-guided behaviour. Indeed, the interactions between this memory system and other cognitive faculties remain relatively uncharted research territory. I will present evidence from behavioural, neuroimaging and neuropsychological studies to clarify the cognitive and neural mechanisms that govern the interactions of VWM with other cognitive faculties in the healthy, aging, or diseased brain.