The Functional Dissociation Research Between Visual-object And Visual-spatial Information Processing In Visuo-spatial Sketchpad

The visuo-spatial sketchpad is one of four components in the working memory model, recently a range of researches focus on the functional dissociation between visual-object and visual-spatial information in visuo-spatial sketchpad. The visual-object working memory component maintain and operate visual information like pattern, shape, and color while spatial working memory component is to actively manipulate the spatial information like location and movement, but they are not separate completely. We agree with the view that visual-object and visual-spatial working memory is distinct, but they have the common component, and carry out related research. Our study includes three experiments, in the prior two experiments we employs real Chinese character and artificial novel character as stimuli, and makes use of change detection paradigm to explore the functional dissociation in different distraction. There are three independent variable: stimuli, space position and distraction, and the dependent variable is reaction time and correct percentage. The task of experiment 1 is object recognition. The result is that the main effect of stimuli, space position and distraction are significant, and there are marked interaction effect between stimuli and space position, stimuli and distraction. The assignment of experiment 2 is to recognize space position. We found that the same result as experiment 1, besides the interaction effect between space position and distraction is significant while the dependent variable is correct percentage. The results of two experiment proved the previous hypothesis, that is there are crossed area between visual-object and visual-spatial working memory though they are disparate, changes of space position can influence the memory of object, and different objects also affect the judgment of space position. In addition distraction have prominent impact on visual-object and visual-spatial working memory. The third experiment explores ERP technique for measuring the changes of brain wave while participants operate task about the functional dissociation between object and spatial working memory, we employ four spatial oriented words as stimuli, and use change detection paradigm to ask participants to recognize spatial oriented word or its space position according to special request. The result shows that two working memory tasks activate P2,N2,P3 components, but only in the N2 component the main effect of task is obvious, there are more positive move in space working memory than in object working memory. In addition, the main effect of working memory task in the amplitude of P3 component is notable, but there is no main effect of task in of the latency period of P3, and the difference wave and its map express that the activation is most obvious in the former central area.