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The Functional Working Memory Architecture of Visual Change Detection Tasks: Are These Tasks Visual Domain Specific?

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Abstract

This thesis aimed to investigate the functional working memory architecture of two visual change detection tasks; a quantitative colour change detection task (Luck & Vogel, 1997) and a qualitative Size Just Noticeable Differences task (Phillips & Hamilton, 2001). Domain specific approaches to the working memory architecture proposed the use of visual only representations (Baddeley, 2012), however, multicomponent approaches, have suggested the use of both visual and verbal representations (Logie, 2011; Brown & Wesley, 2013). The current thesis examined this issue using six experimental investigations. The first two studies piloted the two tasks. Two consecutive studies used dual task interference protocols to investigate the working memory architecture of each change detection task before study five provided electrophysiological data. The final study of the thesis then aimed to discover if both change detection tasks could predict verbal and non-verbal intelligence in children aged 7-13 years. The pilot investigations indicated the appropriate array size and shape size stimuli to use for the remainder of the thesis. Both dual task studies then indicated the use of visual and verbal representations within each change detection task, however qualitative smaller changes were not susceptible to verbal interference. Further evidence was provided from the electrophysiological data presenting activation of the semantic N400 and visual specific N200 in both change detection procedures, but this was significantly reduced in the small change, qualitative stimuli. Results of the final developmental investigation also indicated a more visual specific approach to the qualitative task; leading the current thesis to propose a context-dependent multicomponent approach to change detection protocols. Results are discussed in relation to the multicomponent and attentional models of working memory.
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... Of particular interest, the aim is to clarify these distinct relationships with both verbal and non-verbal intelligence, using regression methods to show how visual working memory can contribute to the development of intelligence. Current researchers will aim to use a task created in the work of Jenkins (2016) which utilised a change detection paradigm, designed to assess working memory in terms of 5-20% changes in shape size. This task was seen as a coordinate measure as it measured the fine details that could be stored within visual working memory. ...
... In previous research from Jenkins (2016), the importance of different percentage changes was highlighted, with the suggestion of differences between smaller 5-10% changes, and larger 15-20% changes. As this piece of research is using the coordinate visual working memory task from Jenkins (2016), regression analyses on the coordinate task were conducted separating the data for the 5%, 10%, 15% and 20% changes. ...
... In previous research from Jenkins (2016), the importance of different percentage changes was highlighted, with the suggestion of differences between smaller 5-10% changes, and larger 15-20% changes. As this piece of research is using the coordinate visual working memory task from Jenkins (2016), regression analyses on the coordinate task were conducted separating the data for the 5%, 10%, 15% and 20% changes. ...
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The associations between visual working memory and intelligence have been extensively investigated in adults and children, in particular with the focus of smaller coordinate changes in visual arrays. Research has suggested that the association between coordinate measures of working memory of intelligence is non-existent within an adult context. However, more recent developmental research has suggested a contrast in a younger sample. In a novel use of a change detection protocol, using 90 children aged 7–13 years, the current research aimed to clarify the relationship between a coordinate measure of visual working memory and both verbal and non-verbal intelligence. It was found that the coordinate measure of visual working memory performance was a significant predictor of both verbal and non-verbal intelligence, in particular the 5% changes within the coordinate arrays. Results are discussed in terms of the future use of such visual working memory tasks with a particular emphasis of the use of 5% visual array changes.
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