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In this thesis we study various dissipative processes that are associated with the flow of an atomic Bose-Einstein condensate at zero temperature. In particular, we investigate the effect of a weak correlated disorder potential on the collective dipole motion of a harmonically-confined elongated condensate. By using an extension of the Harmonic Potential Theorem, we demonstrate that the dynamics of the system can be described equivalently in terms of a disorder potential oscillating relative to a stationary condensate. This latter point of view allows the application of linear response theory to determine the drag force experienced by the condensate and to evaluate the damping rate of the centre of mass oscillation. The density response function for the elongated condensate is determined with a new local density approximation that takes into account the tight radial confinement of the atomic cloud. Our linear response theory reveals the detailed dependence of the damping rate on various system parameters. A comparison with available experimental data is only partially successful and points to the need for additional experiments. In addition to disorder induced dissipation, we also consider a variety of other problems that can be addressed by means of linear response theory. For example, we study momentum transferred to a condensate by a Bragg pulse and the energy absorption of a gas in an optical lattice that is parametrically modulated in different ways. All of these applications demonstrate the utility of linear response theory in describing the dynamics of Bose-condensed systems which are subjected to weak perturbations. / Thesis (Ph.D, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-04-26 10:54:11.915

Most contemporary schizophrenia research indicates that a heritable neurointegrative deficit may be a vulnerability marker for schizophrenia spectrum disorders. Researchers often measure this deficit in terms of impaired attention on a vigilance task, the Continuous Performance Test (CPT). Impaired attention is found not only in floridly psychotic schizophrenics, but also in remitted schizophrenics, children biologically at risk for schizophrenia, and young adults psychometrically identified as at risk for schizophrenia spectrum disorders. Findings from these investigations provide a possible link in the diathesis-stress model of schizophrenia genesis. However, little research attention has been paid to the potential interactive effects that attentional impairments and interpersonal relations may have in determining susceptibility to active schizophrenic symptomatology. In this study, 703 undergraduates completed measures of interpersonal attachment, perceived relations with parents and peers in childhood, positive schizotypy (schizophrenism) and negative schizotypy (anhedonia). Based upon their schizotypy scores, 191 of these participants were selected to complete a version of the CPT that, by degrading visual stimuli and presenting them very briefly, rapidly produces decrements in vigilance. In a staggered random design, CPT participants were assigned to one of three motivational induction conditions designed either to increase intrinsic motivation, decrease intrinsic motivation, or to replicate the standard CPT protocol. Path modelling supported a bidirectional relationship between adult attachment and schizophrenism. For female participants, recalled relations with fathers and childhood peers, but not with mothers, predicted adult attachment: for males, recalled relations with mothers, fathers, and childhood peers all predicted adult attachment. Maternal and paternal relations had no direct relationship to schizophrenism, while childhood peer relations and adult attachment were substantially related to schizophrenism for both sexes. Using signal detection indices and growth curve analysis across six blocks of CPT performance, the motivational induction designed to increase intrinsic motivation was found to attenuate the decrement in vigilance across time, while the motivational induction designed to decrease intrinsic motivation was found to augment the vigilance decrement, compared to the standard CPT protocol. Perceptual sensitivity scores were lower for high schizotypy participants than for low schizotypy participants, such that anhedonic (negative) and schizophrenism (positive) schizotypy interacted to predict the most impaired performance. High schizotypy participants had lowered perceptual sensitivity scores throughout the CPT protocol, but did not show a more rapid decrement in vigilance compared to others. Participants who reported low levels of intrinsic motivation or positive emotion, or who demonstrated diminished persistence in a hand held dynometer task, also had lowered perceptual sensitivity scores. This relationship was most strong for self-reported intrinsic motivation. Intrinsic motivation was unrelated to schizotypy, and there were no interactions between self-reported intrinsic motivation, schizotypy, and the experimental motivational inductions. High levels of motivation appeared to compensate partially for the impaired attentional performance associated with schizotypy. Contrary to expectations, no interactions between interpersonal attachment and attentional performance were predictive of schizotypal tendencies. Results indicate the importance of the experimental setting as an interpersonal occasion that can either support or undermine attentional performance. The substantial relationship between motivation and attentional performance indicates that future CPT research should include measures of motivation, and that schizophrenia-related deficits in attention may be at least partially eliminated by increasing intrinsic motivation. / This thesis was digitized as part of a project begun in 2014 to increase the number of Duke psychology theses available online. The digitization project was spearheaded by Ciara Healy.

ABSTRACT Over the last few years Bipolar Disorder has been associated with chronic neuropsychological deficits that remain even when episodes of depression, mania or hypomania remit. Furthermore Bipolar Disorder has been associated with progressive cognitive impairment, leading to the description of the illness as chronic and deteriorating, rather than as an illness with discreet episodes from which patients can fully recover. The results of neuropsychological studies have been criticized for methodological weaknesses however. The present study attempted to address these weaknesses. The aim was primarily to establish whether neuropsychological impairment exists in euthymic patients, and secondarily, to establish if neuropsychological functioning deteriorates with illness severity. Sixteen euthymic Bipolar I disordered patients were matched for age and sex to 16 controls and subjected to a battery of neuropsychological tests. Matched pair T-tests were used to identify if significant differences in neuropsychological functioning existed between the two groups. The ANOVA technique was used to determine if neuropsychological functioning deteriorated with illness severity. Markers of illness severity utilised in this study were number of depressive episodes, number of manic episodes, number of suicide attempts and number of hospitalisations. The results indicated that neuropsychological differences between the patient and control group were minimal and not clinically significant. The present study sample was medically and psychologically well managed and enjoyed good support structures and their neuropsychological functioning did not deteriorate with illness severity. It was concluded that the sample size and the nature of the sample selected could perhaps have affected the study outcome. It was therefore hypothesized that bipolar disorder is not a homogenous group and that protective factors may exist which affect the course and outcome of the illness. These protective factors should be the subject of further investigation as they are likely to significantly impact on the natural history of this disease process.

The aim of this research was to describe the borderline individual’s lived experience of inhibiting self-mutilation and thus capacity for healthy functioning. A question which would elicit a description of the experience o f this phenomena was formulated. Three self-mutilators were interviewed and the two psychologically richest narratives were chosen for the research. Based on phenomenological methodology the two protocols were analysed in detail. From the results it becomes clear that borderline individuals are ambivalent when attempting to inhibit self-mutilation. Although they have a need to be self-sufficient and through a process of trial and error find the method of inhibiting that best suits them, it appears difficult for such individuals to trust that they have this ability and thr hnsr resources to find such a method. Borderline personality structure may be viewed along a continuum. The technique chosen by the individual is likely to fit with where they are developmental^ in relation to this continuum. Hence, while each individual may or may not make use of transitional objects within their techniques, they do have a need to draw on ‘soothers’. Although the ‘soothers’ may vary with regard to shape and form, they do appear to share similar qualities and to become imbued with like meanings by the individuals. The ‘soothers’ create a safe and holding space which is empathic, attuning, non-judgmental and non-directive in its interaction with the borderline individual. ‘Soothers’ need to allow the individual a sense of mastery and control over their otherwise chaotic environment. Repeated use of ‘soothers’ allows the borderline individual to begin drawing on good introjects as opposed to negative introjects which serves to increase confidence, sense o f self and the ability to trust in their own inner resources. This pin points an area of healthy functioning in the individual with borderline structure which until presently has been overlooked in the literature on the functioning of those with borderline structure

Objectives: - The present research attempts to elicit children's perceptions and experiences of enduring a road traffic accident (RTA). It also examined their parents experiences of parenting such children and their own experiences and perceptions of the accident. Participants: - The study focussed on 14 children, aged from 9 years 9 months - 14 years and 4 months of age who had endured a RTA from between 9-33 months previously and their parents. Design: - The study employed a non-experimental design with a combination of quantitative and qualitative paradigms. Method: - The participants were identified via the hospital database of all children who had endured a RTA from between 6-24 months previously. Both the children and their parents were interviewed on specifically designed semi-structured interview schedules. Each interview was then tape-recorded and transcribed in its entirety. These transcripts then provided the universe of material for subsequent qualitative analysis. Results:- The results of this study demonstrated that approximately half of the children who had experienced a RTA were suffering from a post traumatic stress disorder (PTSD). In addition, the PTSD case children differed from the non-case children on factors such as awareness of the inpending RTA, feelings of self-blame regarding the accident, and more negative thoughts regarding their experience immediately after the impact and at the time of the assessment. In addition, the parents of the case children displayed similar responses to that of their children. Conclusion: - A theoretical Model was presented to account for the main findings in response to the research questions, also drawing on existing research. It is emphasised that this model is speculative due to the small sample size insofar as it draws upon the present findings, and as such can only relate to this study sample and further research would be required to fully test and validate it. In addition, recommendations were made for service delivery and clinical practice.

Little is known about the experience of families of children with autism spectrum disorder (ASD) in community settings. The purpose of this research is to learn about the family experience when visiting a science museum, focusing on the motivations of the family, environmental features of the museum, strategies used by family members, and definitions of a successful visit to the museum. Data were collected through semistructured interviews and observations of four families that included a child with ASD. The families in this study appear to want the same community experiences for their children as families with typically developing children. Both the motivations for the visit and features of the environment appeared to influence the family’s approach and strategies they employed for a successful visit. Strategies included those completed before the visit (visitor planning strategies), as well as during the visit (strategies at the museum). The strategies enabled families to enjoy and experience success within the museum environment. The information learned in this study may help families with a child with ASD prepare for and use features of the museum to enjoy successful museum visits. Recommendations are provided for museums seeking to create inclusive opportunities for all families.

Thesis (M.D.)--Boston University

Obsessive-compulsive disorder (OCD) is a common psychiatric illness characterised by recurrent, intrusive thoughts and repetitive, stereotyped behaviours. There is converging evidence that OCD is associated with a specific cognitive deficit related to organising and manipulating information in working memory. There is also evidence that OCD is associated with certain pre-morbid personality traits. However, further research is needed to elucidate whether these cognitive deficits and personality traits are specific to OCD or are present in other anxiety disorders and/or individuals with sub-clinical levels of obsessive-compulsive (OC) symptoms. In this thesis, 20 OCD patients were compared to 20 patients with panic disorder, 20 subjects with sub-clinical OC symptoms and 20 healthy control subjects on tests of working memory and the Five-Factor Model of personality. To measure different aspects of working memory, participants completed three delayed matching-to-sample (DMS) tasks and two continuous performance working memory tasks (n-back tasks). The DMS tasks assessed the ability to actively maintain different types of information in working memory (irregular objects; geometric objects; spatial locations). The n-back tasks assessed the ability to update and temporally order verbal and spatial stimuli in working memory. The OCD patients were less accurate than the healthy control subjects on the memory trials of the spatial DMS task, the 3- back trials of the spatial n-back task, and the 2-back and 3-back trials of the verbal n-back task. The OCD patients were also less accurate than patients with panic disorder and sub-clinical OC subjects on the verbal 3-back task. The results indicated that OCD patients were impaired on cognitive tasks requiring the maintenance of spatial stimuli and the updating and temporal ordering of verbal and spatial stimuli in working memory. The OCD patients were not impaired on tasks requiring the maintenance of object information in working memory. To measure normal personality traits, subjects completed the Revised NEO Personality Inventory (NEO PIR). Compared to healthy controls, OCD patients reported being highly emotional and introverted, less open to new experiences, and lacking confidence in their own abilities. The OCD patients were similar to the panic disorder patients on most of the domains and facets of the NEO PI-R, however, they were distinguished by their lower openness to experiencing new activities, and being less diligent and purposeful. Compared to the sub-clinical OC subjects, OCD patients reported being more prone to feelings of depression, more vulnerable to stress, less likely to experience positive emotions, more humble and sincere and less able to carry tasks through to completion. Overall, the thesis provided further evidence that OCD patients are impaired on cognitive tasks requiring the organisation and manipulation of information in working memory. However, it is still unclear whether this deficit arises due to capacity constraints being exceeded in working memory systems, or some other executive dysfunction such as excessive error monitoring. Future research, combining neuropsychological testing with neuroimaging techniques, is required to better understand the neural mechanisms underlying the impaired performance of OCD patients on tests of working memory. The present thesis also found that normal personality traits � as measured by the NEO PI-R � were able to distinguish OCD patients from healthy controls, patients with panic disorder and individuals with sub-clinical levels of OC symptoms. The results have implications for sub-clinical OC research and the clinical management of OCD.

Aim: In this study, women were interviewed about their experiences of recovering from an eating disorder - The aim has been to investigate the factors that contributed to recovery and with guidance of these factors, find factors that can be used in a preventive intervention. Method : A qualitative approach was used to design and conduct interviews, the design of the study was descriptive and a semistructured interview was used. The local affiliation of The Swedish Eating Disorder Association was contacted and provided contact with 10 women who participated in the interview. To participate in the study the women had to be recovered from their eating disorder for at least two years. The women who patricipated in the study were between 22 and 36 years old and had been recovered for 2- 16 years. Data were analyzed and coded then categories with similar themes about the factors that were important for recovery wad etablished. The various groups were summarized and are then recognized in the results. Results: Various factors have been important for recovery. One outstanding factor was people in their surroundings and people they met in treatment such as therapist, doctors and psychologists. These were persons who contributed to their courage to leave the eating disorders and helped them to better self-esteem, self-respect and hope for the future. Other important factors included the re- finding of their interests and to be their own selves in social contexts. Another important factor was to read literature about eating disorders, and biographies about people who have recovered from eating disorders. The conclusion is that the most important factor in recovering from an eating disorder is a person´s environment and its support. In order to prevent eating disorders, the work in the first place should be given to encourage children and young people´s self esteem