Abstract
Visual working memory (VWM) temporarily stores and manipulates a very limited set of visual information. In the past 15 years, the majority of the current VWM studies have focused on its storage mechanisms. However, few studies has been involved in the ‘working’ characteristic of VWM, one of which is selective maintenance. Recent researchers have attempted to explore the underlying mechanisms of VWM in selectively maintaining objects presented at distinct locations. However, the selective maintenance mechanisms over the constituent features of object have not been explored before. The current project aimed at exploring this issue. Particularly, according to the interactive model of perception and VWM, we hypothesized that the selective maintenance of object-feature depends on the characteristics of object: There are distinct mechanisms on selective maintenance between object containing fine-grained information (colored-polygons) and object composed of highly-discriminable features (colored-shapes). We tested this hypothesis by adopting the retro-cue paradigm combined with visual search task. In our study, an object composed two features was initially memorized. During the maintenance phase, we presented a retro-cue to inform participants to selectively retain one feature and drop another, and then require participants to complete a visual search task. If the selective maintenance of object-feature exists, the search time would not be prolonged significantly when the ignored feature appears as distracter. In line with our prediction, we found that the ignored features could capture attention in visual search task when colored-shapes were presented as memory stimuli (Experiment 1), while the ignored polygon could not when colored-ploygons were presented as memory stimuli (Experiment 2), suggesting that selective maintenance could occur for the object composed of fine-grained features but could not occur for the object composed of highly-discriminable information. This research reveals there exists dissociable mechanism when VWM selectively maintaining object features.