Behavioral And ERP Study: The Effect Of Visual Masking On Visual Working Memory

In the visual processing system,the visual working memory(VWM)has important implications for the real-time processing and storage of the visual information.In recent years,along with the visual working memory more and more attention,researchers have acquired a lot of research results in the aspects of visual working memory capacity,precision and visual memory storage mechanism.Visual working memory can filter the information which is needed by itself from a variety of external visual information,while excluding the irrelevant information or interference information,and conduct preliminary processing and storage about the selected information.Therefore,the researchers pay more attention to the problem of the mechanism about the visual working memory processing irrelevant information or interference information.This research proceeds from the masking condition’s visual working memory,and focuses on discussing the effect of the visual mask(mask property and quantity)on visual working memory when it process on the different quantity’s objects while it is under the different visual masking conditions.The research takes the color as the stimulation for the visual working memory,using the behavioral experiment and Event-Related Potential Technique to reflect the number of storage object’s CDA elements as EEG index,and discussing the visual mask reflection of visual working memory from the mask property and quantity.The study includes two parts: each part adopts the masked change detection task,and uses the behavior and Event-Related Potential(ERP)technology to gather and analyze the research results.The first part discusses the effect on the visual working memory processing of the dissimilar visual masking stimulus.The author finds the visual mask’s effect on the visual working memory relative to the similarity of the mask stimulus except for the stimulus onset asynchrony(SOA).When the masker stimulation is similar with memory object,it will have greater impact of visual working memory performance.Through analyzing CDA element theauthor finds the influential effect on masking stimulus is coming mainly from the first 100 ms on the consciousness of the mask,that means 400 ~ 500 ms after the memory items appears.The similar mask effect is greater than dissimilar mask and the masker stimulation amounts almost have a multiple relation.The second part discusses the effect on the different number of mask stimulus during the visual working memory processing the color information.The different number of masks has different effects on visual working memory,and the more masks the greater influence.The effect mainly comes when the memory item appears 400~500 ms,that is the stage of the mask stimulation consciousness.Also,the author finds that the mask quality and quantity do not have a multiple relation and the mask quantity relates to memory load.Under high memory load,full masking effect is larger than half masking effect.For the two-part study of the original ERP wave analysis,it finds in 350~450ms time window,masking type and the number of masking in the memory field of vision contralateral and ipsilateral brain regions have different inhibition effect on visual working memory.