The Structure and Capacity of Visual Working Memory: Effects of Aging.

To identify an object one must identify not only its parts and components, but the ways in which these parts and components combine to make a meaningful representation (Chalfonte & Johnson, 1996). When attention is focused on a particular location we engage in the "integration" or "conjunction" of the various features that characterise that location (Treisman & Gelade, 1980). The relational information about the object, its surroundings, and temporal placement are integrated or “bound” together to make a complex memory of the object and its occurrence (Wheeler & Treisman, 2002). Therefore complex memories not only require memory for particular features, but also certain cognitive processes for binding these features together. The process of binding features to form integrated objects seems to be affected by aging. Research has shown that older adults have impaired memory for binding information together to form complex memories of non-words (Naveh-Benjamin, 2000), coloured objects in various locations (Chalfonte, & Johnson, 1996; Mitchell, Johnson, Raye & D'Esposito, 2000) , and names paired with faces (Sperling et al., 2000). This research project was addressed to examine the nature of the binding deficit seen in older adults. Before moving on into the different sections of this work, I will provide a theoretical frame about current trends within the binding of information in working memory in elderly and younger people. Firstly, I will focus on work supporting the effect of the aging on binding information in working memory. Secondly, some relevant research done on the binding of features in working memory will be outlined. Thirdly, functional magnetic resonance imaging (fMRI) data relevant to the binding deficit in elderly adults will be presented. Finally, Alzheimer's disease, a condition associated with age, that presents remarkable deficits in the association of information in memory will be presented