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.

On the functional independence of numerical acuity and visual working memory.

Deciding where to direct our vehicle in a crowded parking area or where to line up at an airport gateway relies on our ability to appraise the numerosity of multitudes at a glimpse and react accordingly. Approximating numerosities without actually counting is an ontogenetically and phylogenetically primordial ability, given its presence in human infants shortly after birth, and in primate and non-primate animal species. Prior research in the field suggested that numerosity approximation is a ballistic automatism that has little to do with human cognition as commonly intended. Here, we measured visual working memory capacity using a state-of-the-art change detection task and numerosity approximation using a dot-comparison task, and found a null correlation between these two parametrical domains. By checking the evidential strength of the tested correlation using both classic and Bayesian analytical approaches, as well as the construct validity for working memory capacity and numerosity approximation estimates, we concluded that the present psychophysical evidence was sufficiently strong to support the view that visual working memory and numerosity approximation are likely to rely on functionally independent stages of processing of the human cognitive architecture.

The role of perceptual similarities in determining the asymmetric mixed-category advantage.

Considering working memory capacity limitations, representing all relevant data simultaneously is unlikely. What remains unclear is why some items are better remembered than others when all data are equally relevant. While trying to answer this question, the literature has identified a pattern named the mixed-category benefit in which performance is enhanced when presenting stimuli from different categories as compared to presenting a similar number of items that all belong to just one category. Moreover, previous studies revealed an asymmetry in performance while mixing certain categories, suggesting that not all categories benefit equally from being mixed. In a series of three change-detection experiments, the present study investigated the role of low-level perceptual similarities between categories in determining the mixed-category asymmetric advantages. Our primary conclusion is that items' similarity at the perceptual level has a significant role in the asymmetric performance in the mixed-category phenomenon. We measured sensitivity (d') to detect a change between sample and test displays and found that the mixed-category advantage dropped when the mixed categories shared basic features. Furthermore, we found that sensitivity to novel items was impaired when presented with another category sharing its basic features. Finally, increasing the encoding interval improved performance for the novel items, but novel items' performance was still impaired when these items were mixed with another category that shared their basic features. Our findings highlight the significant role low-level similarities play in the asymmetric mixed-category performances, for both novel and familiar categories. (PsycInfo Database Record (c) 2024 APA, all rights reserved).