The Asymmetry Between The Upward And Downward Arcs On Working Memory

The upward arc is an arc that arches up,a downward arc is an arc that arches down,and an up and down arc refers to an upward and down arc.Zhang Xiao(2016)found that the upward arc in the upper field of vision has a memory advantage compared with the downward arc in the lower field of vision,indicating that the arc memory has the advantage effect of the upper field of vision.This study was aim to investigate the asymmetry of upward and downward arcs on working memory when the visual field difference disappeared.In this study,upward and downward arcs were mainly used as visual stimuli.In Experiment 1 and Experiment 2,arc memory tasks with different detection methods were used.In Experiment 1,the detection method was reappearance,and in Experiment 2,the detection method was recognition.Experiment 2 and Experiment 3 used different experimental designs.Experiment 2 was randomly presented with arcs with different orientations,while Experiment 3 used a block design,that is,there was only one orientations of arcs in a block.Experiment 1 was a behavioral experiment,howerver,Experiment 2 and Experiment 3 studied the brain mechanism of upward and downward arc working memory asymmetry using event-related Potentials(ERP)technique.In Experiment 1,a free recall arc memory task was used to explore whether there was an asymmetry effect of upward and downward arcs in working memory.An in-subject design with 2(arc orientation: upward arc,downward arc)× 3(arc height: low,medium,and high)factors was adopted to explore whether the upward arc had a memory advantage by comparing the accuracy of the upward arc and the downward arc.The working memory capacity of the subjects was measured by the change detection task.The results showed that:(1)The memory performance of the upward arc was significantly better than that of the downward arc,and the upward arc had the asymmetric effect of working memory.(2)The higher the arc height,the worse the memory performance;(3)The working memory capacity was independent of the arc orientation.In Experiment 2,we used the arc memory task in the change detection task,and the detection mode was recognition to investigate whether the upward and downward arc asymmetry effect existed in working memory.A single-factor design(arc orientation: upward arc,downward arc)was used to investigate whether the upward arc had a memory advantage by comparing the memory performance of the upward arc and the downward arc.Experiment 2 used a completely random design,that is,in the same block,both upward and downward arcs appeared in a completely random order.The change detection task was used to measure the working memory capacity of the subjects,and the differences of N1 and N2 components of upward and downward arcs in the encoding stage of working memory were explored using ERP technology.The results showed that :(1)The memory performance of the upward arc was significantly better than that of the downward arc,and the upward arc had the asymmetric effect of working memory.(2)The level of working memory capacity was independent of the arc orientation;(3)In the encoding stage of working memory,the N1 component of occipito-temporal region was found to be asymmetrical in the upward and downward arcs,and the downward arcs induced larger negative waves.In Experiment 3,we used the arc memory task in the change detection task.The detection mode was recognition to investigate whether there was an asymmetry effect of upward and downward arcs in working memory.A single-factor design(arc orientation: upward arc,downward arc)was used in the subject,which was the same as Experiment 2.By comparing the memory performance of the upward arc and the downward arc,we explored whether the upward arc had a memory advantage.The only difference is that Experiment 3 adopts block design,that is,within the same block,only upward or downward arcs appear,and the order of upward and downward arcs appears in balance between blocks.Experiment 3 used ERP technique to explore the differences of N1 and N2 components of upward and downward arcs in the encoding stage of working memory.The results showed that :(1)the memory performance of the upward arc was significantly better than that of the downward arc.Compared with the downward arc,the subjects reacted faster to the upward arc and had higher discriminative ability,and the working memory asymmetry effect of the upward arc appeared.(2)In the encoding stage of working memory,the N1 and N2 components of temporal lobe induced larger negative waves than the N1 and N2 components of occipitar lobe induced larger negative waves than the N1 and N2 components of occipitar lobe induced larger negative waves.Three experiments have found that the stability of the arc up and down the asymmetric effect of working memory,this study has two kinds of explanation for this phenomenon:(1)the object working memory of weak object assumption: the object working memory not only affected by the number of objects,also affected by the characteristics of the object,the objects of this study as a single arc memory tasks,task performance,explain fluctuation arcs in different attributes;(2)Attention-based working memory asymmetry: For the upward and downward arcs of working memory,there is a top-down effect of attention.The upward arc is more like a target position for the subject,while the downward arc is more like a non-target position.The location information previously stored in the working memory leads to priority attention to the target location,and the upward arc is more like a prototype of the arc than the downward arc.In summary,this study shows that :(1)the upward arc has an asymmetry in working memory,while the upward arc has an advantage in memory;(2)When the detection mode of arc memory task was different,the asymmetry of upward and downward arc working memory was stable.(3)The working memory asymmetry of the upward and downward arcs was stable in both the completely random design and the block design;(4)In the early attention stage of arc working memory encoding,there will be asymmetry of upward and downward arcs.