Changes
Ronald A. Rensink, Departments of Psychology and Computer Science, University of British Columbia, Vancouver BC, Canada.

Progress in Brain Research, 140: 197-207.   [pdf]

Introduction

All things change, and nothing stays still... - Heraclitus, c.500 BCE.


This past decade has seen a great resurgence of interest in the perception of change. Change has, of course, long been recognized as a phenomenon worthy of study, and vision scientists have given their attention to it at various times in the past (for a review, see Rensink 2002 [Annual Review of Psychology]). But things seem different this time around. This time, there is an emerging belief that instead of being just another visual ability, the perception of change may be something central to our "visual life", and that the mechanisms that underlie it may provide considerable insight into the operation of much of our visual system.

This development may have been sparked by a number of factors: technology that allowed the easy creation of dynamic displays, a feeling in the air that it was time for something new, or it may have simply been a matter of chance. But once underway, this development was fueled by results, results that included both novel behavioral effects and new theoretical insights. Many of these centered around change blindness, the failure of observers to see large changes that are made contingent upon some transient event, such as a brief blank, or a saccade. Given the strength and robustness of these effects, they provide a powerful way to explore a number of issues, such as the extent to which our behavior is based on nonconscious processing of visual input, the way that attention is (and is not) involved in vision, and the extent to which visual information is accumulated across saccades.

The chapters presented in this section provide excellent illustrations of the success of this approach in providing new insights into the operation of our visual system. In what follows, an attempt will be made to consolidate the results and conclusions obtained by each of these studies with a broader theoretical framework based on earlier work. Such an approach will hopefully show that studies of change perception can help resolve a number of important issues in visual perception, and--even more importantly--raise a number of interesting new questions.


Back to The Need for Attention to See Change.