Symposium Summary

Abstract

This symposium brings together the world's leading specialists in six different subareas of visual attention. These distinguished scientists will expose the audience to an enormous range of methods, phenomena, and theories. It's not a workshop; listeners won't learn how to use the methods described, but they will become aware of the existence of diverse methods and what can be learned from them. The participants will aim their talks to target VSS attendees who are not necessarily familiar with the phenomena and theories of visual attention but who can be assumed to have some rudimentary understanding of visual information processing. The talks should be of interest to and understandable by all VSS attendees who have an interest in visual information processing: students, postdocs, academic faculty, research scientists, clinicians, and the symposium participants themselves. Attendees will see examples of the remarkable insights achieved by carefully controlled experiments combined with computational modeling. DeYoe reviews his extraordinary fMRI methods for localizing spatial visual attention in the visual cortex of alert human subjects to measure their “attention maps”. He shows in exquisite detail how top-down attention to local areas in visual space changes the BOLD response (an indicator of neural activity) in corresponding local areas V1 of visual cortex and in adjacent spatiotopic visual processing areas. This work is of fundamental significance in defining the topography of attention and it has important clinical applications. Gallant is the premier exploiter of natural images in the study of visual cortical processing. His work uses computational models to define the neural processes of attention in V4 and throughout the attention hierarchy. Gallant's methods complement DeYoe's in that they reveal functions and purposes of attentional processing that often are overlooked with simple stimuli traditionally used. Ahumada, who introduced the reverse correlation paradigm in vision science, here presents a model for the eye movements in perhaps the simplest search task (which happens also to have practical importance): the search for a small target near horizon between ocean and sky. This is an introduction to the talk by Geisler. Geisler continues the theme of attention as optimizing performance in complex tasks in studies of visual search. He presents a computational model for how attention and stimulus factors jointly control eye movements and search success in arbitrarily complex and difficult search tasks. Eye movements in visual search approach those of an ideal observer in making optimal choices given the available information, and observers adapt (learn) rapidly when the nature of the information changes. Dosher has developed analytic descriptions of attentional processes that enable dissection of attention into three components: stimulus amplification, internal noise reduction, and the sharpening of attention filters. She applies these analyses to show how subjects learn to adjust the components of attention to easy and to difficult tasks. Sperling reviews the methods used to quantitatively describe spatial and temporal attention windows, and to measure the amplification of attended features. He shows that different forms of attention act independently.