A case of integrative visual agnosia (1987)
Riddoch MJ., Humphreys GW.
This chapter presents evidence for a mechanism for optimizing selection of new objects by deprioritizing selection of old objects. It terms the phenomenon of deprioritizing the selection of old objects visual marking. The chapter proposes that visual marking occurs because observers inhibit the locations of old or previously processed objects so that those objects no longer compete as strongly for selection. It shows that marking is a resource-limited intentional process that can be voluntarily switched on relatively rapidly. The chapter also shows that inhibitory marking can be “switched off” in an automatic way by activity in complementary visual processing pathways sensitive to dynamic change. In general terms, visual marking provides valuable survival advantages for observers in relatively complex environments that require monitoring for changes that indicate danger. The chapter considers the top-down attentional inhibition of old locations or distractor features which is related to other recent accounts of selection processes in vision.