Exploring The Mechanism Underlying Attribute Amnesia On The Basis Of Working Memory Characteristics

It is generally assumed that attention plays a crucial role in determining whether information can be encoded into working memory(WM).However,the phenomenon of attribute amnesia(AA)discovered by Chen and Wyble(2015a)challenged this traditional view.Attribute amnesia is a striking phenomenon showing that participants failed to report a specific attended attribute(e.g.,color of a letter)that they had just used for a task(e.g.,reporting the location of the colored letter),if they did not expect to report that information.This phenomenon indicates that attending to a specific piece of information is not sufficient for it to be encoded into WM,and expectation plays a crucial role in memory encoding of attended information.Despite the AA has been repeatedly replicated in a number of studies from different laboratories,the underlying mechanism is still under debate.Two hypotheses regarding the mechanism of AA have been proposed:Memory consolidation deficit hypothesis and Forgetting hypothesis.Memory consolidation deficit hypothesis suggestes that AA reflects a failure to consolidate attended information(i.e.,key attribute)into WM;on the contrary,the Forgetting hypothesis proposes that AA might be caused by forgettting due to the use of a surprise test in which participants need to read and understand the surprise question and respond in a different way.The core debate between these two hypotheses focuses on whether or not the key attribute in AA has been consolidated into WM.None of previous studies could answer this question and therefore,the current study aims to directly address this unsolved issue.Specifically,in this study,on the basis of three different characteristics of working memory,we used a combination of the AA paradigm,WM guide attention paradigm,and the change detection paradigm to test whether or not the key attribute has been consolidated into WM:(1)Experiment 1:Previous studies have shown that WM can guide attention automatically,and this effect could be regarded as a probe index of WM.Thus,we combined a visual search task with the classic attribute amnesia task in Experiment 1,and the results showed that key attribute cannot produce a WM guide attention effect.(2)Experiment 2:Previous studies have shown that only one item in WM can guide attention,whereas none of any items could guide attention if multiple items are simultanously stored in WM.In Experiment 2,participants were asked to store the color of an item in WM while performing the AA task(the key attribute is another color)simultanously.The results revealed that the color in WM could still guide attention,even though it was accompanied by another color(key attribute).(3)Experiment 3:Previous studies have consistently shown that WM capacity is only 3-4 items.In Experiment 3,participants were asked to complete a change detection task(which was used to calculate the WM capacity)and the AA task simultaneously.The results showed that the key attribute did not occupy the WM capacity.The results of above three experiments provided consistent evidence that key attribute in AA has not been consolidated into WM,which thus support the Memory consolidation deficit hypothesis.