Objectives: The aim of this study is to investigate the relationship between perfectionism and quality of life in people with Irritable Bowel Syndrome (IBS). It was hypothesised that people with IBS who score highly on perfectionism will experience a poor quality of life, and that perseverative thinking will mediate this relationship. Methods: A quantitative cross-sectional design was used. Online questionnaires were completed by 418 adults with a diagnosis of IBS. Perfectionism was measured using Hewitt & Flett's Self-Orientated and Socially Prescribed Perfectionism subscales. Other measures included The Perseverative Thinking Questionnaire and IBS Quality of Life. Correlational and regression analyses were performed in SPSS and mediation analyses using Hayes PROCESS for bootstrapping. Results: Self-Orientated and Socially Prescribed Perfectionism were both found to predict poorer IBS quality of life. Perseverative thinking was found to mediate the relationship between both dimensions of perfectionism and IBS quality of life. Moreover, these associations remained after accounting for the effects of age, gender, comorbidity and duration of IBS. Conclusions: People with IBS who have elevated levels of perfectionism are likely to suffer poorer quality of life, and this is mediated through perseverative thinking. This suggests perfectionism and perseverative thinking are possible perpetuating factors of IBS. Clinicians should consider specifically assessing and targeting these areas for intervention among people with IBS.

This thesis is presented in five chapters. Chapter one offers a review of the literature, divided into six sections. The first section of this chapter provides an understanding of cancer as a disease and a public health concern, including detail on its incidence and prevalence, the biology of cancer and its treatment. The second section of this chapter reviews the literature on physical activity and cancer across the cancer continuum, from prevention of cancer, through cancer treatment, living with or beyond cancer, advanced cancer, and detail on physical activity and cancer mortality and recurrence. The third section of this chapter discusses the determinants of physical activity in cancer survivors, framed within behavioural theories and models to support the identification of intervention opportunities. The identified intervention opportunities are covered in the fourth section. The fifth section of this chapter presents the scope and relevance of the research included in this thesis. The sixth section provides a summary of chapter one. Chapter two presents the first study included within this thesis, a service evaluation investigating the reach, adoption, and impact of a training intervention to influence UK healthcare professionals to give very brief advice on physical activity to cancer survivors. This study also includes an assessment of the predictive value of the behavioural theory upon which the intervention is based, the COM-B model of behaviour (Michie, van Stralen, & West, 2011). Chapter two includes four sections covering an introduction, the method, results, and discussion. Chapter three presents the second study within this thesis. The second study is a randomised waiting list control trial to investigate the impacts of a remote-print based intervention supported by Internet-based tools on the physical activity, self-efficacy, and health-related quality of life (HRQOL) of cancer survivors. The randomised waiting list control trial also includes a cost-consequence analysis. Chapter four presents the third study of this thesis, a process evaluation of the remote-print based intervention supported by Internet-based tools. This process evaluation aimed to contextualise use and perceived usefulness of the intervention, supporting the identification of what works and for whom. Chapter five then closes this thesis with a discussion on the theoretical and practical contributions of the body of research as a whole. This final chapter also includes discussion on how the interventions under assessment influence the identified determinants of physical activity in cancer survivors, and identification of future research possibilities.

The overall aim of this research is to identify the impact of a brief, low-cost mindfulness meditation training program for employees in a workplace setting, specifically in the UK higher education sector. Although there has been extensive research on the efficacy of mindfulness training for perceived stress of employees, to date, there has been limited research exploring the following: (a) impact of mindfulness-based training interventions on work-related outcomes (b) long-term impact of those interventions, and (c) use of self-help training interventions (low-cost) without supplementary guidance. This thesis aimed to address the research gaps through three empirical studies. Firstly, Study 1 used a randomised waitlist control trial design (N = 125) to assess the impact of offering a mindfulness-based intervention to employees. Intention-to-treat analysis showed improvements in mindfulness and perceived stress after the offer of the Headspace® app. With higher levels of participation, results showed progressively greater improvements in mindfulness, perceived stress and two work-related outcomes, work-life-balance and emotional job engagement. Study 2 then used a longitudinal (12 months) repeated-measures design (N = 60) to investigate the extent to which the amount of Headspace app usage predicted mindfulness, perceived stress and work-related outcomes. Simple regression analysis showed that higher Headspace usage led to greater improvements in work-life-balance and emotional job engagement, however other outcomes were not significant. Study 3 used a qualitative design (N = 13) to explore participants' 12-months experiences of practicing mindfulness, and the perceived impact on their workplace issues. From a thematic analysis of phone interview transcripts, three themes evolved: challenges (workplace related), selective focus (experience of mindfulness), and work impact (from more mindful approach to workplace). Overall, the findings from this thesis provide support for the effectiveness of brief mindfulness-based training in improving mindfulness and perceived stress. The findings demonstrate that those who use a mindfulness training app can improve their work-life balance and emotional job engagement within two months and both work-related outcomes can be improved with increased usage over one year, although improvements do not increase in mindfulness and perceived stress, and other work-related outcomes. Finally, this thesis contributes to research on the use of digital smart-phone apps as an effective delivery method of mindfulness-based training.

The sense of agency (SoA) refers to the feeling of control towards our actions and their effects in the outside world. The aim of this thesis was to study SoA to gain a better understanding of it and how it originated, particularly in light of the cue integration approach to SoA. Additionally, this work aimed to bring greater understanding of agency changes in populations where there has been little or no agency research. To achieve this, we used paradigms that created agentic uncertainty by modulating external agency cues. We found that the susceptibility to manipulation of external agency cues predicted schizotypy scores in healthy adults. We also showed that SoA in patients with anosognosia for hemiplegia is overall dominated by their intention to move, while external agency cues are discounted. When examining changes in SoA throughout adulthood, our results suggested that older adults rely more on internal agency cues and discount external cues; we showed that this is potentially a result of increased reliance on internal agency cues. For the first time, we investigated changes in SoA in people with Mirror-touch synaesthesia. We found that their experience of agency is more malleable than in non-synaesthetes, perhaps due to an enhanced saliency of external cues in the creation of SoA. Having tested SoA in these groups, we looked at the neural mechanisms that might be responsible for the observed SoA changes. We used transcranial Direct Current Stimulation to test the contribution of right Temporo Parietal Junction to agency processing, in response to the same tasks used in the previous chapters. Lastly, we investigated the relationship between sense of agency and sense of ownership, a theme running throughout this thesis. We suggest that the cue integration approach is a valid framework to understand SoA and discuss future directions.

High anxiety may relate to the enhanced processing of threat-related stimuli, enhanced cognitive distraction, and/or altered conflict resolution. It was the purpose of this thesis to carry out a series of behavioural experiments designed to tap into these neuro-cognitive functions. Facial stimuli were used in computerised reaction time experiments. Personality traits were assessed using psychometric measures. The primary aim of this thesis was to determine how trait anxiety (and social anxiety) relates to the recognition of emotional facial expressions, how trait anxiety relates to distraction by other emotional faces (or emotional words) when identifying emotional facial expressions, how trait anxiety relates to differences in how emotional conflict resolution is achieved, and to determine how trait anxiety relates to other personality traits. Moreover this work aimed to develop a novel emotional face conflict resolution paradigm that is grounded in neuroscientific theory. Results showed that high trait and social anxiety are (differentially) related to the enhanced processing of threat-related faces, but provided no evidence that trait anxiety is related to distraction caused by peripheral emotional faces (threat-related or otherwise). However, we found a very specific distracting effect of happy words that was related to trait anxiety. We found that trait anxiety was somewhat related to conflict resolution but further work is required before this relationship can be properly understood. These results are discussed in detail, in relation to established theories of anxiety. My original contribution to knowledge is a detailed analysis of how sub-clinical levels of anxiety relate to emotional face discrimination, emotional distraction (when emotional face discrimination is required), and emotional conflict resolution (when emotional face discrimination is required). My original contribution to knowledge is also a detailed examination of how sub-clinical anxiety relates to other personality constructs, and the development of a novel but scientifically grounded emotional face flanker task.

Resource allocation is an important context in which children and adolescents learn about moral issues of equality, equity and fair exchange. Recent research has examined resource allocation in an intergroup context in an attempt to understand how group processes exert an influence upon the propensity to share fairly. This thesis extends existing knowledge by providing an in-depth examination of a key element of the intergroup world; namely, social norms. Specifically, how the ability to coordinate multiple social norms when allocating resources in a challenging intergroup context develops between middle childhood and adolescence. Chapter One provides an overview of literature regarding resource allocation in an intergroup context, as well as relevant theory. In Chapter Two when ingroup and outgroup norms of competition and cooperation were manipulated, participants coordinated multiple norms at the peer level when allocating resources. In Chapter Three, adolescents and young adults coordinated peer group and generic societal norms, whereas children relied predominantly on ingroup norms to guide their allocation. Chapter Four demonstrated age-related differences between children and young adults in understanding of group processes when evaluating ingroup members who deviated from a resource allocation norm. In Chapter Five children coordinated generic norms at the classroom level with ingroup norms in their allocation decisions. Finally, Chapter Six examined the influence of peer norms in a situation of intergroup inequality. Adolescents coordinated their understanding of relative advantage and group processes, whilst children allocated equally. Overall these studies demonstrate the development of resource allocation strategies that simultaneously coordinate peer level norms, generic societal norms, and contextual information. In Chapter Seven, the findings are discussed in the context of theory and potential explanatory mechanisms are explored.

Impulsivity-related personality traits have been found to be related to increased substance use, while religiosity and spirituality have been shown to reduce substance use behaviours. This thesis aimed to study possible interactive effects of risk and resilience factors on young adult substance use behaviours in multicultural communities using samples from Western countries and the Middle East. A study of 245 UK university students found self-control to be significantly related to problematic alcohol and cannabis use. The study also identified sensation seeking and fun seeking as strong predictors of cannabis use. Some of these findings were replicated in a sample of 173 university students from Lebanon. The study found fun seeking to be significantly related to problematic alcohol use. A moderating effect of religiosity on the relationship between impulsivity and substance use behaviours was also identified. A study of 191 university students in the United Arab Emirates found urgency and lack of premeditation to be strongly related to problematic dokha use. This study also identified a moderating effect of religiosity on the relationship between impulsivity and alcohol consumption. Lastly, negative urgency was shown to be strongly related to shisha consumption in a study of 80 young adults residing in the United Arab Emirates. Religiosity was also shown to be a moderator of the relationship between impulsivity and shisha use. The cultural aspects of these findings was discussed in detail. The final study of the thesis considered how risk-taking behaviours can be associated with alcohol use among a group of young adults residing in the United Arab Emirates. These findings help to further understand cultural differences in substance use behaviours, and contribute to theoretical models of risk for substance use disorders worldwide.

Vicarious perception describes our ability to co-represent the experiences of others, by matching observed states onto representations of our own experience. For instance, seeing another person feel touch or pain elicits activity in regions associated with first-hand touch and pain sensation, including somatosensory cortices. Vicarious touch and pain perception is thought to facilitate complex social processes such as empathy, and also shows substantial inter-individual variability. For a minority of people, a physical sensation of touch (mirror-touch synaesthesia) or pain (conscious vicarious pain) is felt on their own body when observing someone experience the same sensation. Current theory suggests increased excitability in somatosensory cortices may underlie conscious vicarious experience. Recently, broader impairments in self-other distinction have also been implicated. This thesis first attempted to modulate vicarious tactile perception with transcranial current stimulation targeted at somatosensory cortices or the right temporo-parietal junction (linked to self-other control). A lack of modulation provided minimal support for either somatosensory excitability or self-other distinction accounts. Behaviourally, conscious vicarious pain responders and control participants did not significantly differ in self-other control abilities. Additional self-other distinction processes (beyond self-other control) were next considered. This revealed atypical bodily self-awareness in conscious vicarious pain responders. Lastly, perception of animacy was modulated by stimulus and perceiver variability, but did not significantly differ between mirror-touch synaesthetes and controls, providing implications for vicarious perception from inanimate stimuli. Collectively, this thesis highlights broader impairments involved in conscious vicarious perception, and the importance of the sense of bodily self-awareness for social perception and interaction in typical adults.

Social anxiety in young people is common and impairing. Maladaptive parenting has been associated with the onset and maintenance of anxiety in children and adolescents, but the extent and nature of this association with regard to social anxiety has not yet been comprehensively examined. A systematic review was conducted of studies investigating associations between parenting and social anxiety disorder and symptoms in children and adolescents, which identified 37 studies. The results of these studies were mixed, but overall provided support for an association between dimensions of parental control, rejection and anxious rearing and child and adolescent social anxiety. Methodological shortcomings of the studies and limitations of the review mean that these results should be interpreted with some caution. Future studies should be conducted in clinical populations, using longitudinal designs and independent assessment methods, in order to clarify the impact of maladaptive parenting on offspring social anxiety. This may further inform theoretical models and the development of effective treatments for social anxiety in children and adolescents.

Background: Fatigue is a complex, multifactorial and multidimensional phenomenon, which has been described as a persistent overwhelming sense of tiredness, weakness, or exhaustion. It is the third most common concern for patients with inflammatory bowel disease (IBD), experienced by 44-86% of patients with active disease and 22-41% of patients in remission. Fatigue can have a significant negative impact on patients’ quality of life (QoL). The aetiology of fatigue is not well understood. Interventions for IBD-fatigue are scarce, demonstrating limited benefit, and have not been implemented into clinical practice. The development of a theoretically-driven intervention to improve fatigue is a primary need for this population. Methods: The overall aim of the study was to develop a complex intervention for the management of IBD-fatigue and test its feasibility and potential efficacy. Guided by self-regulation theory and the Medical Research Council framework for development, feasibility and piloting phases, four steps were conducted in an iterative process. A systematic review study (Paper 1), identified aetiological modifiable factors which had already been or could be targeted by health interventions to improve IBD-fatigue. A quantitative cross-sectional study (n = 182) (Paper 2), evaluated the potential relationship between the identified modifiable cognitive-behavioural factors and IBD-fatigue. Patient and public involvement activities informed the adaptation of a cognitive-behavioural therapy (CBT) intervention for multiple-sclerosis fatigue to IBD-fatigue. Lastly, a two-arm pilot randomised controlled trial (RCT) with a nested qualitative study (Papers 3 and 4) assessed the feasibility and initial estimates of efficacy of a CBT manual with 8, weekly therapist telephone session (n = 15) vs. a fatigue information sheet without help (n = 16). Results: Initial estimates of efficacy with per protocol analysis showed a reduction in fatigue scores and an improvement in QoL scores at 3-months post-randomisation. The difference in change in scores between groups was significant for impact of fatigue. The intervention was acceptable to participants and feasible for therapists to deliver. Healthcare professionals working with IBD patients reported that the intervention would be broadly applicable but time, finance and training constraints may limit its implementation in routine clinical care. Conclusions: CBT for IBD-fatigue is feasible and has a potential for improvement of the impact of fatigue on daily activities. A large-scale RCT is needed to investigate the size and longevity of treatment gains and the cost-effectiveness of the therapy. Incorporating changes to the protocol and developing an online intervention may be an effective way to overcome the barriers to implementation identified by healthcare professionals and test the generalisability of the intervention to IBD-clinical practice.