The influence of self-relevant information on attention and memory

Attention and memory can increase the saliency of information in accordance with task goals (Driver, 2001; Pashler & Sutherland, 1998; Reinecke, Rinck, & Becker, 2006; Vuilleumier, 2005). Self-relevance of stimulus materials may be an important factor, both in attention and memory. However, there is, as yet, no clear consensus on the mechanisms underlying this. For example, it is unclear if the benefit of self-relevance on attention and memory is because of positive emotional value linked to the self or if self-relevance and emotion are two separate processes. This thesis independently assessed the contributions of self and emotional processing on attention and memory. The experiments use a modified version of a paradigm developed by Sui, He and Humphries (2012). These experiments arbitrarily assigned visual information as being self-related or not self-related. Furthermore, the emotional valence of these stimuli is also varied. The studies explored whether the emotionality and self-relevance influence memory for the presented materials and whether they do so independently or interactively. The studies explored the effects of emotional self-relevance on attention and memory using a combination of behavioural and neurophysiological methods. The findings of this thesis support previous research on the benefits of self-relevance, on both attention (Sui, He, & Humphreys, 2012; Sui, Sun, Peng, & Humphreys, 2014; Wang, Humphreys, & Sui, 2016) and memory (M. A. Conway & Dewhurst, 1995; Kelley et al., 2002; Klein & Kihlstrom, 1986). The results also showed that emotion has similar effects on attention and memory as self-relevance does. This thesis has shown that the underlying processes of self and emotion are distinct (Experiment 1). However, this thesis has also shown in a novel way that emotional self-relevant information is processed more efficiently than either emotion or self-relatedness alone (Experiment 2). In other words, self-relevance and emotion can interact and together increase the saliency of emotional self-related memories (Experiment 6). The results also revealed that, though self-related information is processed faster and more efficiently, this was only in terms of the faster rate of learning for self-related information compared to other-related information. When given enough repetitions, non-self-related information can achieve a similar level of memorability, given sufficient exposure (Experiment 3, and Experiment 4). Nonetheless, the richer information linked to self-related events means that all things being equal, such information will tend to produce more stable memories over time (Experiment 5), which results in faster forgetting of other-related information compared to self-relevant information. These findings are further supported by the Electroencephalogram (EEG) research of this thesis. In particular, early N100 responses were found to be enhanced for self-related items during the matching task. In memory, the late positive parietal components linked to recollection were more enhanced for self-related information also. Overall, the EEG results support the suggestion that self-related information has attentional priority and, consequently, is encoded into memory more efficiently than other-related information. Fundamentally, this thesis has shown that attention prioritises self-relevant information over information unrelated to the self. Moreover, it showed that self-relevance interacts with emotion, and in doing so ensures enriched and therefore, more salient memories. This thesis is the first to show that prioritised (emotional) self-relevant information is recalled more often as well, when compared to information unrelated to the self. The importance of this interaction between emotion and self-relevance is discussed in terms of potential broader clinical benefits for people suffering from memory impairments.

Grantor dc:publisher

Oxford Brookes University

Year dc:date

2019

Author dc:creator

• Veldhuis, Alfred

Contributors dc:contributor

• Pilling, Michael
• Kumar, Sanjay
• Rathbone, Clare

Statement dc:rights

• All rights reserved

Language dc:language

en

DOI dc:identifier

https://doi.org/10.24384/xk7m-vb69

OAI identifier oai:identifier

tle:66418716-ef4a-4519-b263-f1894e2194dd:d6bd9758-527a-46cd-bfe2-c433766e8fca:1