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Mindfulness training cultivates momentary awareness, a form of attention directed to non-evaluative, immediate sensation. This form of attention stands in contrast to a more temporally extended awareness, which allows for the evaluative organization of experience into a personal narrative. The neural mechanisms underlying such awareness, and their role in regulating emotions, are poorly understood. Thus, in three functional magnetic resonance imaging (fMRI) experiments, I explored the thesis that momentary and extended awareness represent dissociable modes of self-reference, with momentary self-reference reducing ruminative elaboration of events by biasing attention towards interoceptive signals from the body. I compared individuals who were randomly-assigned to either an 8-week Mindfulness-Based Stress Reduction (MBSR) training course against a waitlisted group (Controls). Three distinct studies examined the impact of Mindfulness on: 1) the contrast between explicitly directed momentary and extended self referential processing; 2) reactions to an induced sadness challenge; and 3) the contrast between interoceptive (breath-monitoring) and exteroceptive (visual) attention. In all three studies MBSR led to a shift in neural activity away from cortical midline structures, such as the medial prefrontal and posterior cingulate cortices, to predominantly right-lateralized viscerosomatic structures, and specifically the insular cortex. Cortical midline activity is thought to support habitual patterns of evaluation, and stands as the neural correlate of a narrated, extended self, while right-lateralized insula activity is thought to represent the recurrent integration of present moment context, the neural correlate of the momentary self. These data revealed that MBSR may enhance the distinction between momentary and extended self-reference, reducing cortical midline responses and recruiting a novel, right-lateralized viscerosomatic network. Additionally, MBSR graduates demonstrated reduced emotional reactivity to a film-based sadness mood induction, reducing cortical midline activity and inhibition of the right insula. Moreover, the MBSR group demonstrated enhanced right middle insula recruitment during the monitoring of sensory experience associated with breath monitoring, a core mindfulness practice. The data from this final study also suggest that MBSR promoted an integration of posterior insular sensory representations with anterior insular subjective representations of present moment status. Preserved viscerosomatic activity in the face of emotional challenge may be a predictor of enhanced well-being following mindfulness training.

[Truncated abstract] Auditory hallucinations are some of the most distressing and disabling symptoms of schizophrenia. However very little is known about the exact processes responsible for auditory hallucinations. The aim of this thesis is to provide a new perspective on the nature of the cognitive deficits underlying auditory hallucinations in schizophrenia. As a preliminary study to the investigation of auditory hallucinations in schizophrenia, a factor analysis of a measure of hallucinatory predisposition, the Launay- Slade Hallucination Scale-Revised (Bentall & Slade, 1985), was carried out on data from a large sample of undergraduate students (N = 562). An overlap in characteristics between hallucinatory-like experiences in normal individuals and auditory hallucinations in schizophrenia should draw attention to factors that are important to the hallucinatory experience in general. One of the findings from this study was that intrusiveness is a commonly reported characteristic of hallucinatory-like experiences in normal individuals. Intrusiveness is also one of the defining features of auditory hallucinations in schizophrenia. Since the process of inhibition is essential for suppressing unwanted thoughts, the first set of two studies using patients with schizophrenia (N = 43) investigated the presence of an (intentional) inhibition failure in auditory hallucinations using the Hayling Sentence Completion Test (HSCT; Burgess & Shallice, 1996) and the Inhibition of Currently Irrelevant Memories Task (ICIM; Schnider & Ptak, 1999). It was found that auditory hallucinations were linked to a deficit in intentional inhibition as measured by these tasks. The process of inhibition was further investigated using the Affective Shifting task, but auditory hallucinations were not associated with a deficit on this task. Possible differences in the inhibitory demands of the HSCT, ICIM and Affective Shifting tasks are discussed.

Thesis (Ph. D.)--University of North Texas, Aug., 2007. / Title from title page display. Includes bibliographical references.

Thesis (PhD) - Swinburne University of Technology, Brain Sciences Institute, 2007. / A thesis for Doctorate of Philosophy, Brain Sciences Institute, Swinburne University of Technology - 2007. Typescript. Bibliography: p. 245-285.

Thesis (Ph.D.)--Georgetown University, 2009. / Includes bibliographical references.

Thesis (Ph.D.)--University of Western Sydney, 2008. / A thesis presented to the University of Western Sydney, College of Arts, MARCS Auditory Laboratories, in fulfilment of the requirements for the degree of Doctor of Philosophy. Includes bibliographies.

Thesis (Ph.D.)--University of Western Sydney, 2009. / A thesis presented to the University of Western Sydney, College of Arts, School of Humanities and Languages, in fulfilment of the requirements for the degree of Doctor of Philosphy. Includes bibliographies.

Thesis (M.Sc.)--University of Ottawa, 2008. / Includes bibliographies.

Thesis (M.Sc.)--University of Ottawa, 2008. / Includes bibliographies.