The Bias Effect Of Ensemble Statistics On The Storage Of Real-World Objects In Visual Working Memory

Visual working memory is a limited-capacity memory system for temporarily storing visual information during information processing(Baddeley,1986,2000;Baddeley,Allen,& Hitch,2011).In order to expend the capacity of visual working memory,observers have developed efficient and flexible memory strategies,such as chunking,binding and ensemble statistics representation.It had found that when there are multiple items in the display,observers can quickly and accurately compute ensemble statistics.For example,previous studies on ensemble statistics representation of simple stimuli have found that there is a set representation based on color(Brady & Alvarez,2011).This can not only save cognitive resources,but also improve the overall memory efficiency.Moreover,ensemble statistics representation can regulate the storage of items in visual working memory.However,previous studies focused on simple stimulus,ignored the effect of ensemble statistics representation for real-world objects.A lots of studies have shown that,unlike simple stimulus,real-world objects have both perceptual features and category information that from long-term memory experience.Is the real-world object representation in visual working memory also regulated by the ensemble statistics representation? If such a representation exists,is it based on features,or category information,or based on the combination of features and category information? For these questions,the current studies didn’t have a clear answer.This study explores the following questions:(1)whether real-world object representation in visual working memory is affected by ensemble statistics representation base on colors;(2)whether real-world object representation in visual working memory is affected by ensemble statistics representation base on category information;(3)whether real-world object representation in visual working memory can have a feature-based and category-based ensemble statistics representation when both the color visual category information exist simultaneously,and ensemble statistics representation based on which way has a greater impact on the visual working memory of a single items.Using the color-related task,the results of Experiment 1 found that real-world objects have a color-based ensemble statistics representation in visual working memory;Experiment 2 uses the color-independent task and found that there is also have a color-based ensemble statistics representation.Experiment 3 and Experiment 4 used category-related and category-independent tasks respectively found that real-world object representation in visual working memory were affected by the category-based ensemble statistics representation.In Experiment 5,when both color and category information existed,the observers were able to form a color-based and category-based ensemble statistics representation,and the ensemble statistics representation based on category information had a greater impact on the visual working memory representation of single items.