Different Cognitive Styles Of Individual Behavior In The Spatial Working Memory Task And Erp Study

Visuo-spatial working memory refers to cognitive functions that allow individuals to temporarily maintain and manipulate visual and(or) spatial information, is a important subsystem of working memory. From middle period of the nineties of the twentieth century, the psychologists and the researchers of cognitive neuroscience had made a lot of experiments about problem that visuo-spatial working memory could separate(Oberauer, 2000, 2003; Chen, 2000; Jonides and Smith, 1997, 1999; Bosch 2001), advantage of subsystems in visuo-spatial working memory(Luck, 1997, Liu & Wang, 2003), activation position of subsystems in visuo-spatial working memory(Jonides and Smith, 1999; Bosch, 2001; Wang & Lin, 2004),individual ifference of working memory, and had acquired plentiful study conclusion. Study of visuo-spatial working memory became a important problem in domain of cognitive neuroscience. Understanding how and why people differ from each other is a fundamental goal , which can enable us to analyses the mental function and its relational theory much more exactly. There is still a lack of study on neural mechanism of individual difference of visuo-spatial working memory at present. According to the visual cognitive style, the so-called"spatial versus object visualizers", proposed by Kozhevnikov(2002, 2005), we explored neural mechanism of individual difference of visuo-spatial working memory through advanced Event-related potentials technique.To be concrete, the results were as follows:1. When high-load object working memory task was processed,the condition of maintenance stage affected spatial visualizer'memory significantly, which indicate that the score of memory in short maintenance stage was better than that in long delayed stage.2. In object working memory task, the load of task affected the score of memory both for the spatial visualizer and the object visualizer. However, the initial seconds in the maintenance stage failed to make a contribution.3. In spatial working memory task, the load of task affected the score of memory both for the spatial visualizer and the object visualizer with more influences on the latter.4. When high-load spatial working memory task was processed,the sore of the spatial visualizer was better than the object visualizer. 5. When the different participant of visual cognitive style encoded object information, there was not significant difference in speed of encoding, brain energy resource used to encode and elaboration level of encoding.6. There was memory-load effect in individual difference of brain mechanism in object working memory. When low-load and high-load object working memory task was processed at middle and later stage of encoding, there is no difference in the intensity of activation in all topographical region of interes between spatial visualizer and object visualizer. Intensity of activation in left fronto-central cortex of object visualizer was stronger than spatial visualizer when high-load object memory task was processed at early and middle stage of maintenance. There was not similarly significant difference in the low-load object working memory task.7. When the different participant of visual cognitive style encoded spatial information, there was not significant difference in speed of encoding, brain energy resource used to encode and elaboration level of encoding.8. A similar memory-load effect was found in individual difference of brain mechanism in spatial working memory. When low-load spatial working memory task was processed at middle and later stage of encoding, intensity of activation in left fronto-central cortex of object visualizer was stronger than spatial visualizer. When high-load spatial working memory task was processed at middle and later stage of encoding, intensity of activation in prefrontal cortex of object visualizer was stronger than spatial visualizer. When low-load and high-load spatial working memory task was processed at stage of maintenance, intensity of activation in all topographical region of interes was no difference between spatial visualizer and object visualizer,but the rehearsal and retaining of spatial information of the spatial visualizer initiated earlier than object visualizer.