The Effect of Practice on Visual Change Detection in Computer Displays

Abstract

People are sometimes unable to detect changes in their field of view, especially when the change coincides with a distraction. This failure to detect visual changes is known as change blindness. Our research on change blindness is motivated by the increasing use of complex digital displays in both military and industrial process control systems. We are interested in the extent to which important changes in displayed information might be missed, and methods to decrease vulnerability to change blindness. The present study examined whether practice detecting specific changes would lead to better change detection performance in general. Participants practiced detecting specific visual changes, such as an icon changing from blue to red, using the flicker paradigm with feedback given after each trial. Practice did lead to improved detection performance for the practiced changes (i.e. the blue to red changes). As performance improved, reaction time declined as well. To assess the generality of this effect, following practice, participants were given a transfer test in which changes that had not occurred during practice were scheduled (e.g., green to yellow changes or icon shape changes). Performance on these novel changes was significantly worse than for the practiced changes and there was no significant difference between the within-category changes (such as green to yellow instead of blue to red), and the between-category novel changes (the shape changes). These results therefore suggest that the improvements observed were specific to the changes practiced. On the other hand, the possibility exists that the procedure used actually taught participants to ignore the features that changed in transfer. During practice, these features were presented, but never changed. If participants learned to ignore these features during practice, that would work to oppose any generalization of heightened visual attention. This and other factors that may have affected performance are discussed.