Abstract
The relationship between the object and the context in which it is embedded affects the episodic recognition memory for that object. The relationship between the object and its background scene defines how strongly they are bound and consequently this affects the memory for encountered episodes. Our studies examine how changes in background context influence memory for objects over time when modulating the relationship between the target object and its background context. We changed the relationship by manipulating target animacy in Exp.1 and semantic congruence with the background scene in Exp.2. In both experiments we presented observers with either 216 unique inanimate or animate objects (Exp.1) or semantically congruent or incongruent to the scene objects (Exp.2) in 432 real world scenes. Each target object was presented twice during the study phase, either in the same background or in a new background. At test, targets appeared either in the same context that they were studied in, or in a new background scene. Object memory was tested using a two alternative forced choice recognition task immediately following the study phase, after a 24-hr delay, and after a 1-week delay. The findings show that over time memory for target objects declined overall, linearly decreasing. However, this was due to different mechanisms at different time points. We observed a robust facilitation effect when the background context was reinstated at test as well as a detriment to object memory when it did change between study and test with different dynamics emerging across the span of 1-week. Animacy of the object did not affect the memory for the objects but it’s semantic congruence to the scene did. Breaking the object-to-scene binding, only when it is strong, during encoding by presenting the target object in different background contexts at study maintains memory for target objects long-term.