Normal and abnormal attentional dwell time: constrains of temporal coding in visual attention in neurological patients and normal individuals

[摘要] This thesis is concerned with the analysis of constrains of temporal coding in visual selective attention. It is well known that despite the great amount of visual information present in the environment the human visual system is only capable to attend and select some of it. How the brain is able to selectively prioritize relevant information and de-prioritize the irrelevant information in order to guide us through space, has been extensively investigated (Treisman and Gelade, 1980; Posner, 1980). Less is known about how this occurs over time. In the present thesis I investigate the role of temporal limitation of selective attention in brain damaged patients and in normal participants by using a simplified version (attentional dwell time paradigm, Duncan et al., 1994), of the Attentional Blink (AB) paradigm which involves the identification of two or more visual targets when stimuli are presented rapidly in temporal succession always at one location (Broadbent and Broadbent, 1987; Raymond, Shapiro and Arnell, 1992). Within this paradigm I have manipulated different factors which may influence this limitation such as: temporal binding, perceptual similarity among stimuli, task switching, integration of audio-visual information and working memory. In addition, by examining the AB in different brain lesioned groups, this thesis attempts to throws light on the neural mechanisms underlying temporal coding and selection. Evidence was provided of the influence of all these mechanisms in coding, selecting and consolidating visual information over time which suggest a multi components nature of temporal selection as well as possible involvements of a temporo-parietal network (Corbetta and Shulman, 2002) which governs their integration.

[发布机构] University:University of Birmingham;Department:School of Psychology

[关键词] B Philosophy. Psychology. Religion;BF Psychology