The Impact Of The Processing Of Chunk By Individual Differences In Working Memory And Memory Load

"Chunk" was first used by Miller to interpret short-term memory span in 1965, it refers to combine the number of units into a meaningful, larger information units of memory unit, with the further study on memory, Baddeley and Hitch (1974) put forward a working memory model, they have a new understanding about "chunk" that it is different between working memory chunk and short-memory chunk, working memory chunk is little representation for processing which embodies the limited working memory capacity, it is a unit of processing information which is able to bind a number of independent stimulus together while maintained in a high accessible states for the upcoming cognitive processing.In order to integrate the relationship between storage and processing in working memory, Oberauer (2002) proposed the working memory concentric model which promotes the studies on chunk to a new level. Working memory is divided into three different functional areas in concentric model, the activated part of long-term memory with infinite capacity, the region of direct access holding 4 items or chunks, the focus of attention holding 1 item or chunk. Oberauer and Bialkova (2009) first proposed two new concept of chunk:ordered chunk and free chunk in a study about the function of focus of attention. The ordered-chunking assumes that elements are bundled in a fixed order within the chunk, so that each is assigned a fixed role. The free-chunking assumes that elements are not linked to a fixed order within the chunk, so that the chunk can be reused while the elements in it swap their roles.the chunk in this study is different from the one Miller proposed, the former is more inclined to a kind of "dynamic" chunk processing, while the latter is a "static" processing unit.Basing on the Oberauer & Bialkova's study in 2009, we discuss the congnitive mechanism of the two new chunks processing in two experiments. The aim of this study is to explore whether the new chunk processing is affected by individual differences in working memory and memory load and Similarities and differences between the two new chunk processing, to verify the concentric model of working memory further. in order to distinguish individual differences in working memory better, we used two types of test tasks. on one hand, we use complex working memory span tasks and n-back task to distinguish individual differences in working memory in experiment 1 and 2 respectively, one the other hand, we change the memory load by varying the number of memorizing stimulus.For each experiment is composed by a part and b part, part a of mental arithmetic processing tasks, part b of spatial reasoning tasks. The conclusions indicate that:1. With the increase of memory load, the level of processing of the two new chunk have a remarkable decline which verify the effect of Set-size effect.2. Individual differences in working memory have no influence on the processing level of two kinds of chunk which is measured by complex working memory span tasks, but there is a Significant difference in the processing level of two kinds of chunk between high and low working memory individuals which is distinguished by n-back task, the results further verify the separation of the region of direct access and the focus of attention in the concentric model of working memory, and also shows that the cognitive mechanism of two types of chunk could be regarded as one aspect of the ability of executive Control.3. Through further analysis of part a and part b results, the study shows that although the two kinds of processing of chunk have a strong commonality in cognitive mechanism, there show some different results between the two types of chunk. One reason may be that ordered chunk is more dependence on executive Control than free chunk; the other reason may be the difference of task demands between the two types of chunk.