Manipulation of interference in the passive visual store

Three experiments are reported that examine the circumstances under which i rrelevant material causes interference with visual memory. Experiment 1 ind icates that the amount of interference is related to the extent of the dyna mic aspect within a visual noise field when the field is used as the irrele vant material. When the dynamic aspect comprises only a single dot changing within a field of 80 x 80 dots, interference is significant. Experiments 2 and 3 indicate that when the dot is extracted from the noise field and pre sented against a uniform plain background interference crucially depends on whether the dot is presented and re-presented at the same spatial location or at different locations. Only when the dot occupies successively differe nt locations is interference caused. It is argued that the results are to b e understood in terms of the two component parts of the VSSP. When the dot is presented against a uniform field and in different spatial locations, in terference acts through the active spatial component. When the dot occupies a single position, interference acts through the passive visual store. The passive visual store only is sensitive to the visual noise background.