The human visual system is sensitive to 2nd-order image properties (often called texture properties). Spatial gradients in certain 2nd-order properties are edge-based, in that contours are effortlessly perceived through a rapid segmentation process. Others, however, are region-based, in that they require regional integration in order to be discriminated. The five studies reported in this thesis explore these mechanisms of 2nd-order vision, referred to respectively as segmentation and discrimination. Study one compares the segmentation and discrimination of 2nd-order stimuli and uses flicker-defined-form to demonstrate that the former may be subserved by phase-insensitive mechanisms. In study two, through testing of a neuropsychological patient, it is shown that 2nd-order segmentation is achieved relatively early in the visual system and, contrary to some claims, does not require the region termed human “V4”. Study three demonstrates, through selective adaptation aftereffects, that orientation variance (a 2nd-order regional property) is encoded by a dedicated mechanism tuned broadly to high and low variance and insensitive to low-level pattern information. Furthermore, the finding that the variance-specific aftereffect is limited to a retinotopic (not spatiotopic) reference frame, and that a neuropsychological patient with mid- to high-level visual cortical damage retains some sensitivity to variance, suggests that this regional property may be encoded at an earlier cortical site than previously assumed. Study four examines how cues from different 2nd-order channels are temporally integrated to allow cue-invariant segmentation. Results from testing a patient with bilateral lateral occipital damage and from selective visual field testing in normal observers suggest that this is achieved prior to the level of lateral occipital complex, but at least at the level of V2. The final study demonstrates that objects that are segmented rapidly by 2nd-order channels are processed at a sufficiently high cortical level as to allow object-based attention without those objects ever reaching awareness.

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The purpose of this thesis was to develop an understanding of active school travel and to investigate the effects of a school-based intervention within the context of an extension of the theory of planned behaviour (Ajzen, 1985, 1991). Specifically, the focus was on understanding the role of habit and cognition in guiding intention and behaviour. This focus was addressed in four studies. The first two studies addressed measurement issues in this area: Study 1 examining the validity and reliability of the Self Report Habit Index (SRHI; Verplanken & Orbell, 2003) as a measure of habit and study 2 examining the validity of a measure of active travel cognition. The third study examined the theory of planned behaviour and the role of habit in predicting active school travel intention and behaviour. Finally, the fourth study examined the effect of a school-based active travel intervention, the Travelling Green resource, at changing these constructs. The findings from the research in this thesis emphasised the importance of both cognition and habit in the prediction of behaviour. However, the ability to change these constructs through the Travelling Green resource was not demonstrated. The implications of these findings in terms of direction for future research and practice are discussed in the final chapter of this thesis.

Aims: The aims of this research were to explore significant client-identified disclosures that occurred in therapy; specifically, (a) to understand the context, or the factors that contributed to the disclosures, (b) to investigate the process of the disclosure event itself and (c) to track the effects of the disclosure to the end of therapy and beyond. Method: This investigation consisted of a pilot study and a principal study, consisting of six clients who were each interviewed about one significant disclosure that they identified in a session of therapy. The data from both studies were analysed using Comprehensive Process Analysis (CPA), a discoveryoriented, interpretive method. A cross-analysis was then carried out to identify themes, followed by a frequency analysis; finally, an expectancy analysis was carried out to investigate the possible effects of researcher bias. Results: All the clients in the principal study planned to disclose in advance. Although the allian ce was a factor, significant disclosures were not necessarily associated with the presence of a warm, close bond with the therapist. Female clients, older than the therapist, disclosed despite doubts. Important disclosures were generally marked by the client's hesitant, tentative speech and a deepening of experience at one minute after the event. Clients experienced disclosing as helpful, especially when this was recognised by the therapist, as it was the first step to assimilating puzzling and painful material; discussion of the significance of the disclosed material helped progress in therapy. The significance and helpfulness of the disclosures appeared to last over time. Implications for practice: This study provides initial evidence that clients are active in planning disclosures in therapy; therapists may facilitate such disclosures by an awareness of discourse markers, such as hesitant speech, and by attending to covert processes, as well as recognising and acknowledging when a client makes a significant disclosure.

Cognitive behavioural models of social anxiety (i.e. Clark & Wells, 1995; Rapee & Heimberg, 1997) conflict in their predictions regarding attention to facial expressions/gestures. Clark and Wells predict that anxiety is maintained in a social situation by decreased attention towards social cues, precipitated by increased self-focused attention. This results in missed opportunities for positive reinforcement from approving audience responses. Rapee and Heimberg argue that attention is split between imagining ones' own performance and scanning the audience for signs of social disapproval. Therefore, the aim of this thesis was to investigate the role of self-relevance and attention in emotional cue processing. Studies 1-3 investigated cognitive processes in face perception using static face paradigms. The results of an eye tracking composite face task (Study 1) indicated that emotion categorisation occurred rapidly and independently of context. However the effect of viewing an emotion al face on the observer involved higher cognitive processes such as prior expectations and self-relevance. In an online composite face categorisation task (Study 2) socially anxious individuals reported that they focused less on angry eyes when categorising a threatening face than less socially anxious participants. Furthermore, in an eye tracking antisaccade task (Study 3), socially anxious participants processed emotional faces with greater attentional control than neutral faces. Taken together these studies suggest that processing differences may account for attentional biases in socially anxious individuals but attention appears to be independent of context in static face paradigms. In studies 4 and 5, processing efficiency was investigated using dynamic video clips. When the social threat was moderate in an emotion categorisation task 19 (Study 4), socially anxious individuals processed social cues more efficiently and interpreted ambiguous social cues more negatively than less anxious individuals, however, efficiency was slowed when the threat was heightened during a live speech eye tracking task (Study 5). Despite increased attention to emotional compared to neutral faces as the task progressed, no evidence was found for group differences in attention to social cues. However, there were group differences in awareness of social cues and socially anxious participants demonstrated lower self-confidence post-task. This suggests that biased interpretations of social cues in performance situations may not depend on biased attentional processes.

The purpose of this thesis was to aid the development of a physical activity and sedentary behaviour intervention for children and adolescents (youth) with Type 1 diabetes. Chapter 1 introduces the research area, target population and design of the thesis. Published guidance on the early development phase of complex health interventions was followed (Campbell et al., 2000; Craig et al., 2008), with three studies being undertaken as part of the thesis. The first study determined physical activity and sedentary behaviour levels and patterns using accelerometers, as well as quality of life using questionnaires, in a sample of Scottish youth with Type 1 diabetes. The second study systematically reviewed the evidence on study characteristics, intervention design and efficacy of phyiscal activity and sedentary behaviour RCT intervention studies in youth with Type 1 diabetes. The third study, developed as two manuscripts, explored perceptions of physical activity and sedentary behaviour and support needs in youth with Type 1 diabetes in patients, their parents, diabetes professionals and schoolteachers using interviews and focus groups. The novel findings of the studies in this thesis in relation to youth with Type 1 diabetes are: the need to target this population group due to low physical activity and high sedentary behaviour participation (study 1); the need for unsupervised, theory based interventions targeting sedentary behaviour in addition to physical activity and high quality evidence to support the efficacy of physical activity on health (study 2); and the requirement of parental and peer support in interventions, the necessity for diabetes professionals to encourage physical activity and the need for better support and training for schoolteachers to accommodate physical activity in schools (study 3). The final chapter of this thesis discusses how the findings of the studies can be used in future research and practice.

This thesis used an attributional framework to examine parental cognitions of behaviour of children with a learning disability (LD), in particular how they predict parent and child behaviour and how these views compare to prevailing societal views of disability. Four studies were carried out. The first study assessed views prevailing among parents of typically developing (TD) children of children with an LD and compared these to views held by parents of children with an LD. Parents of children with an LD overall complied to these prevailing views of LD. A small group of parents holding more affirmative views was identified and these parents made corresponding affirmative choices for their child. The second study was qualitative and investigated the views of parents of children with an LD more in-depth by evaluating views on causes of misbehaviour. Both causes relating to the LD and more typical causes were identified and seemed to affect parenting strategies in different ways. The third study then examined these relationships quantitatively in parents of children with an LD in comparison to parents of TD children. Result showed that parents' attributions predicted strategies differently for each group. An attribution of high child control and low parent responsibility was unsupportive of effective parenting in parents of children with an LD while this was not the case for parents of TD children. The final study subsequently aimed to examine in more detail the underlying structure of parent and child responsibility and control over behaviour in parents of children with an LD and uncovered two different interpretations of responsibility in parents. Implications for theory and measurement of attributions are discussed and suggestions for child behaviour interventions are given.

Past research and theory has suggested that biased attention to substance related stimuli may be an important factor in the development, maintenance and relapse of addictive behaviours and therefore may be a fruitful target for interventions. The current understanding of the extent and roles of substance related attentional biases in addictive behaviours however remains limited primarily as a result of methodological limitations. This thesis examines the extent and roles of substance related attentional bias in social use and dependent use by employing the flicker change blindness paradigm whilst utilising eye tracking and further examines the validity of this methodological approach. Experiment 1a explored alcohol related attentional biases in social users of alcohol. Results demonstrated that a bias in the initial orienting of attention was associated with levels of subjective craving. Additionally analysis indicated that such biases were only evident over multiple trials and when real world scene stimuli were viewed. Experiment 1b examined smoking related attentional biases in dependent smokers and non-smokers and showed that dependent smokers compared to nonsmokers demonstrated a smoking related attentional bias in both grid and real world scene stimuli. However when dependent smokers were analysed by themselves, only a relationship between maintained attention on smoking related stimuli and levels of cigarette use was implicated. Again this later finding was only demonstrated over multiple trials when viewing real world scenes. Whilst experiments 1a and 1b provide evidence demonstrating that sub-components of substance related attentional biases may play differing roles in substance use, they also highlighted the impact of the types of stimuli and number of trials employed when utilising such methodology. Experiments 2a and 2b based on Gilchrist and Harvey (2006) went on to explore the possibility that when using the flicker change blindness paradigm the structure of the stimuli may encourage strategic scanning and so limit the validity of the paradigm as a measure of attentional bias. The results of experiment 2a and 2b demonstrated that when employing the flicker change blindness paradigm, participants display a strategic component in their scan paths from the very first trial, irrespective of the structure of the stimuli. Furthermore, over multiple trials the extent of strategic scanning of both social users of alcohol (experiment 2a) and smokers (experiment 2b) was strongest when viewing the most spatially structured stimuli. However the results were limited in their ability to fully evaluate the relationship between the degree of structure of the stimuli, the extent of strategic scanning and the attentional biases evidenced, possibly as a result of the stimuli composition. Experiments 3a and 3b therefore reanalysed experiments 1a and 1b in order to examine the extent of strategic scanning between perfectly structured grids and complex real world scenes. The results clearly demonstrated that even when real world scene stimuli are utilised when employing the flicker ICB participants still employ strategic scanning, however both experiments demonstrated that it was to a lesser degree than when viewing perfectly structured stimuli. The results of experiments 2a-3b and with the consideration of the pattern of attentional bias results in experiments 1a and 1b outline the effects of the stimuli type on the validity of the flicker ICB task to measure attentional biases and as a result have important implications for future research.

Memory and attention deficits are common sequale following stroke. Despite this, our understanding of these impairments, ways to rehabilitate them and the influence of other variables on these cognitive functions is limited. This thesis incorporates a person-specific methodology to explore in more depth memory and attention problems in long-term stroke survivors. Five studies are reported, the first two are systematic reviews which concluded that there is some evidence in support of memory and attention rehabilitation and physical mobility rehabilitation post-stroke but that the methodological quality of the N-of-1 studies is weak. The second systematic review also revealed that there have been no studies carried out with the aim of increasing overall levels of physical activity in stroke. Studies three and four investigated memory and attention problems in long-term stroke survivors using objective and subjective measures, and assessed the extent to which fluctuations in mood, anxi ety and sleep quality and caregiver psychological and behavioural characteristics influenced self-reported memory and attention. Results showed that long-term stroke survivors experience a range of memory and attention deficits but fluctuation in test performance indicates within-person variability. The studies also showed that memory and attention was temporally associated and predicted by their own mood, anxiety and sleep quality and caregiver mood, anxiety and sleep quality, but the patterns of associations and the effects of the predictors varied across stroke survivors. The final study assessed the feasibility of a combined walking and cognitive training programme with the aim of improving memory and attention. It was concluded that the study was not feasible as it stands. Several methodological amendments would have to be made and then the effects of these changes examined thereafter. Together, the results have implications for the assessment and the rehabilitation of memory and attention functions post-stroke.