The effect of context on pointer allocation in visual working memory.

Visual working memory (VWM) can hold a limited amount of visual information and manipulate it. It encodes this information and forms representations of each one of the relevant objects. When an object changes, VWM can either update or reset its representation to account for this change. To access a specific representation VWM relies on a pointer system associating each representation with the corresponding object in the environment. While previous studies described these processes as reacting to a change in the object status, this study investigated the adaptability of the pointer system to the task context. We measured the contralateral delay activity (CDA; an electrophysiological marker of VWM) as a marker of updating and resetting. In two experiments we used a shape change detection task (similar to Balaban & Luria, 2017) and manipulated the proportion of the resetting and updating trials to create different task contexts. Experiment 1 indicated that VWM can adapt to a resetting mode in which it performs resetting in conditions that triggered updating in previous studies. However, Experiment 2 revealed that the pointer system cannot adapt to an updating mode and perform updating in conditions that trigger resetting. These results suggest that VWM can strategically perform resetting, but once a pointer is lost, it's impossible to update the representation and a resetting process is mandatory triggered regardless of the context.

The go no-go reviewing paradigm: A reliable method for measuring perceptual object-file updating.

The object-file framework explains how object continuity is maintained as objects move: it stipulates that when we focus our attention on an object, we automatically retrieve this object's recent history. Supporting evidence comes from the object-specific preview benefit (OSPB): participants are faster to name a target letter when the same letter appeared in the same versus a different object in a preceding (preview) display. Although this framework has been very influential, replicating the OSPB has proved difficult, presumably because observers could ignore the preview display. To address this problem, a modified object-reviewing paradigm was suggested, which became the standard paradigm: participants are required to report whether the target letter matches one of the preview display's letters. However, as this paradigm makes retrieval of the object's history task-relevant, it is a useful method for studying the structure of object representations for memory but does not capture the automaticity of the object-reviewing process, which is the heart of the object-file account of perception. Here, we suggest an alternative go/no-go object-reviewing paradigm that is specifically tailored to study object-files for perception: it requires participants to attend to the preview display, yet does not require explicit retrieval of the object history. Using our new paradigm, we reliably replicate the OSPB. As a proof of concept, we revisit the persistence of the OSPB, previously investigated with the modified paradigm.