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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Personality Attributes in Clinical Presentation, Measurement, and Treatment

Thalmayer, Amber Gayle 10 October 2013 (has links)
Psychotherapy is sought for diverse problems, and trust in its efficacy has led to increasing parity in insurance coverage for psychological services. But about half of those who begin therapy drop out prematurely, and only about half of those who complete therapy experience significant improvements. Here issues of efficacy measurement and the potential role of personality differences to better guide and assess treatment are explored. It is hoped this knowledge could lead to increased success rates. In terms of outcome measurement, the use and psychometric properties of the Outcome Questionnaire-45 (OQ-45), a popular, brief measure of psychological functioning and change, are assessed. Factor structure is tested in clinical (Study 1) and student (Study 2) samples. Alternative scoring models test whether dimensions of personality drive responses. Using bi-level models, including a total score factor, fit of the intended structure and three- and four-factor personality models was similar. A seven-factor problems model provided the best fit. About half the variance in OQ scores was accounted for by a Big Six personality inventory. The best items for assessing personality attributes in OQ-45 data are noted. Secondly, the relation between personality attributes and clinical presentation and outcomes is explored. Self-report scores on personality attributes predict virtually every life outcome and are highly associated with clinical presentation. Such attributes surely also play a role in treatment, but this association has not been widely studied. In Study 3 the relation of personality attributes to presentation, usage, and outcome is tested in a Couples and Family Therapy clinic sample (N = 222). Neuroticism was strongly associated with initial OQ-45 score, as were other scales (except Openness) to a lesser degree. Being older, more educated, and married predicted attending more sessions, and being older, female, and higher income predicted termination success. Personality scales did not play a role in either outcome. Honesty/Propriety and Neuroticism were, however, associated with steeper decrease in OQ-45 scores over time. / 2015-10-10
52

Neural Correlates of Heart Rate Variability : Threat and Safety Perception

Frändén, Philip January 2018 (has links)
The connection between the heart and the brain was coined 150 years ago by Claude Bernard and has since then been an interesting topic of research. Scientists have for many years searched for biomarkers of stress and health to map the current status of the organism. Heart rate variability (HRV) has been presented as an emerging objective and promising marker to achieve just this. HRV refers to the beat-to-beat variations in heart rate (HR) and is thought to be a useful signal in understanding and providing valuable information of the autonomic nervous system (ANS). HRV has also been proposed as a marker of stress and health by sharing neural correlates and functions with several executive functions. This thesis identified several regions, including the ventromedial prefrontal cortex and the amygdala, in which significant associations across several studies were found between threat and safety perception, emotional regulation and HRV. This suggest that HRV may function as an index of the brain mechanism and structures that guide and govern adaptive functions and thus, provide researchers with valuable information regarding the stress and health of an organism. Two major theoretical frameworks, which articulate and explain the role of HRV as an indicator of individuals ability to adapt to environmental changes and cope under stress is presented. HRV can also be used in practice in several ways and a growing and promising field of application is HRV biofeedback.
53

Entendendo a psicopatia: contribuição dos traços de personalidade e valores humanos / Understanding psychopathy: contribution of personality traits and human values

Monteiro, Renan Pereira 26 February 2014 (has links)
Submitted by Maria Suzana Diniz (msuzanad@hotmail.com) on 2015-11-09T13:22:07Z No. of bitstreams: 1 arquivototal.pdf: 1929344 bytes, checksum: 8bca4e343fc6440e0b9349974c8e79ec (MD5) / Made available in DSpace on 2015-11-09T13:22:07Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1929344 bytes, checksum: 8bca4e343fc6440e0b9349974c8e79ec (MD5) Previous issue date: 2014-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This dissertation aimed at determining the extent to which personality traits, mediated by human values, predict psychopaths phenotypes. In this sense, three empirical studies were carried out. Study 1 aimed to adapt to the Brazilian context the Triarchic Psychopathy Measure (TriPM). Participants were 498 undergraduate students of public and private universities from João Pessoa (Brazil), with a mean age of 22 years (SD = 7.79), they responded to TriPM and demographic questions. Initially, we verified the discriminative power of items, item 35 was eliminated for not differentiate participants with close scores. Subsequently, a Principal Component Analysis was performed by fixing varimax rotation and extraction of three factors, it was possible to identify a solution with acceptable reliability indicators and each dimension being formed by nine items: Disinhibition (α = .73), Boldness (α = .73) and Meanness (α = .81), together explaining 25.6% of the total variance. Study 2 aimed to test the adapted version. Participants were 230 people from the general population, with mean age 26.9 years (SD = 8.87), who responded the TriPM version with 27 items and demographic questions. Alternative models were tested, but the three factors was more acceptable (e.g., GFI = .81; RMSEA = .05). With preliminary evidences attesting to the adequacy of TriPM proceeded to the Study 3, aiming to verify the mediating role of human values in the relationship between personality traits and psychopathy. Participants were 228 undergraduate students of public and private universities from João Pessoa (Brazil), with a mean age of 25.1 years (SD = 7.51) who answered TriPM, Big Five Inventory, the Basic Values Questionnaire and demographic questions. The results indicated that personality traits and values were good predictors of psychopathic phenotypes, moreover, confirmed the mediating role of values in the relationship between personality and psychopathy. It is estimated that the objectives were achieved, with the adaptation of a self-report measure for the estimation of psychopathic traits in general population, with preliminary evidence for its factorial validity and internal consistency, and increasing the understanding that has been around psychopathy from the relationships it establishes with other constructs. / Esta dissertação objetivou verificar em que medida os traços de personalidade, mediado pelos valores humanos, predizem fenótipos psicopatas. Neste sentido, três estudos empíricos foram levados à cabo. O Estudo 1 objetivou adaptar ao contexto brasileiro a Triarchic Psychopathy Measure (TriPM), participando 498 estudantes universitários de instituições públicas e particulares de João Pessoa-PB, com média de idade de 22 anos (DP = 7,79), estes responderam à TriPM e perguntas demográficas. Inicialmente, checou-se o poder discriminativo dos itens, sendo eliminado o item 35 por não diferenciar participantes com pontuações próximas. Posteriormente, por meio de uma Análise dos Componentes Principais, fixando rotação varimax e a extração de três fatores, foi possível verificar uma estrutura com indicadores aceitáveis de fidedignidade, sendo cada dimensão composta por nove itens: Disinhibition (α = 0,73), Boldness (α = 0,73) e Meanness (α = 0,81), explicando conjuntamente 25,6% da variância total. O Estudo 2 objetivou testar a versão ora adaptada, para tanto, participaram 230 pessoas da população em geral, com idade média de 26,9 anos (DP = 8,87) que responderam a versão com 27 itens da TriPM e questões demográficas. Testaram-se modelos alternativos, não obstante, o de três fatores mostrou-se algo mais aceitável (e.g., GFI = 0,81; RMSEA = 0,05), ademais, verificou-se que a estrutura é invariante quanto ao sexo dos participantes. Com evidências preliminares que atestam a adequação da TriPM, partiu-se para o Estudo 3, objetivando verificar o papel mediador dos valores humanos na relação entre traços de personalidade e psicopatia. Participaram 228 estudantes universitários, de instituições públicas e particulares de João Pessoa-PB, com idade média de 25,1 anos (DP = 7,51), que responderam a versão adaptada da TriPM, o Inventário dos Cinco Grandes Fatores da Personalidade, o Questionário dos Valores Básicos e questões demográficas. Os resultados indicaram que traços de personalidade e valores foram bons preditores dos fenótipos psicopatas, ademais, confirmou-se o papel mediador dos valores na relação entre personalidade e psicopatia. Estima-se que os objetivos propostos foram alcançados, com a adaptação de uma medida de autorrelato para a estimação de traços psicopatas na população geral, apresentando evidências preliminares de sua validade fatorial e consistência interna, além de aumentar o entendimento que se tem em torno da psicopatia a partir das relações que ela estabelece com outros construtos.
54

The Effect of an Alcohol Cue on a Risk Taking Task

Logan, Patrick Mcgee 05 November 2015 (has links)
Laboratory-based tasks of impulsivity and related constructs can be useful in predicting alcohol use. Performance on these tasks is generally assumed to reflect traits that remain stable across situations. However, several studies have indicated that manipulations of state-like variables (e.g., mood or stress) can influence levels of impulsivity demonstrated on the tasks. Furthermore, environmental context (in the form of physical setting, or contextual cues) has a demonstrable effect on tasks relevant to alcohol-related risky behaviors (e.g., ad lib drinking tasks). Importantly, this effect of context on behavior is dependent on the individual's alcohol expectancies. It is unknown, however, whether alcohol-related cues would lead to greater risk taking on a commonly used laboratory-based risk task, and whether this effect would be moderated by alcohol expectancies. These hypotheses were tested in a sample of undergraduate social drinkers. Results indicated that participants who viewed an alcohol prime did not perform significantly more riskily on the Balloon Analogue Risk Task than those who viewed a non-alcohol prime. While mean levels of risk taking were higher following the alcohol prime, the difference did not approach significance; the priming condition-by-expectancy interaction was also not significant.
55

Neural correlates of lucid dreaming and comparisons with phenomenological aspects

Lindberg, Markus January 2014 (has links)
Research on the neural correlates of lucid dreaming has recently gained more underlying data. By exploring seven studies that investigated the neural basis of lucid dreaming, this essay sought to examine which neural correlates are associated with lucid dreaming and how proposed neural correlates relate to phenomenological aspects. Dorsolateral prefrontal cortex (DLPFC) was judged as the region most associated with lucid dreaming, in support of a DLPFC hypothesis. Support for reactivation of DLPFC in lucid dreaming consisted of data from electroencephalography, functional magnetic resonance imaging, and transcranial direct current stimulation. Phenomenological aspects associated with this region involved meta-awareness, working-memory, decision-making, and conscious perception. Other regions of interest were parietal areas, frontal areas, and precuneus. Data was not always compatible, implying need for further research. The possibility of further research was judged as promising, based on a recent study inducing lucid dreaming in a significant percent of its test subjects.
56

A cognitive neuroscience perspective of emotions

Lymperopoulou, Ioana Anca January 2015 (has links)
Emotions have a remarkable capacity to mobilize an individual and shape a person’s behavior in order to ultimately lead to a higher wellbeing. The importance of emotions is further emphasized by pathological cases of people who suffer from an inability to normally regulate their emotional life, such as people who suffer from major depression disorder (MDD), eating disorders, or borderline personality disorder. Given the central role emotions play in our lives, it is very easy to understand the great interest cognitive neuroscientists have in this research field. Emotions have been approached in the last decades from different angles and as such, distinct theories arose. The goal of this study is to give a comprehensive overview of the emotion theories that exist, with a focus on three of the fastest developing cognitive theories of emotions: Frijda’s action-readiness, Russell’s core affect and the communicative theory. Additionally, the neural correlates of emotions will be discussed, focusing on the role of amygdala in the negative emotion of fear. Neuroimaging studies that reveal a correlation between the amygdala and emotions, fear in particular, will be described. Given that the ability of self-regulation is crucial for the achievements of our aims and goals, fMRI studies designed to investigate neural the underpinnings of emotion regulation will be presented. The process of cognitive reappraisal will be used to point towards the brain regions that act as down-regulators for the activity of amygdala while processing negatively valenced stimuli.
57

The Influence of Sea Surface Temperature, Chlorophyll Concentration, and Upwelling Index on Kogia Strandings in Florida

Cordero, Vincent U. 01 November 2011 (has links)
It has been demonstrated that certain environmental fluctuations correlate with cetacean strandings in many parts of the world. I examined the correlations between three environmental variables (upwelling coefficient, temperature, and chlorophyll a concentration) and Kogia strandings in Florida from 1998 – 2007. In addition I examined the correlations between El Niño Southern Oscillation (ENSO) events and Kogia strandings in Florida and the southeastern United States (SEUS) from 1977-2007. Florida was divided into four regions and strandings were segregated by region with 76% of the strandings occurring on the east coast of Florida. AVHRR Pathfinder satellite temperature data, and MODIS Aqua and SeaWiFS satellite chlorophyll a data were downloaded from NASA websites; NOAA Fisheries Southwest Fisheries Science Center upwelling data were downloaded from the ERD Live Access Server, and ENSO data were also downloaded from a NOAA website. Upwelling was examined on a per stranding basis. For each stranding, a square region (16 km x 16 km) of ocean adjacent to the stranding was examined for upwelling index values for the two weeks prior to the stranding (in increments of six hours). Each region was divided into 16 sub-regions (4 km x 4 km). For each increment of time the data were averaged over all 16 sub-regions. A significant change in upwelling index was defined as a change of absolute value greater than or equal to 200 m3/s/100 m of coastline. Of the 174 strandings, 91 (52%) were correlated to at least one significant upwelling event within 14 days prior to stranding. I examined upwelling, temperature, and chlorophyll a concentration on a seasonal basis. The Florida coastline was divided into 16 regions. Each region was examined, for all three variables, out to approximately 32 km from shore. For each region the data were averaged for each month over the entire ten year study and compared to the number of strandings in each region each month. Data covering the regions of Florida were merged into four large regions (the east coast, the Keys, the west coast, and the Panhandle). I found an inverse correlation between chlorophyll concentration and strandings in Florida. In addition I found an inverse correlation between upwelling and strandings on the west coast of Florida. I examined the ENSO record from 1977 to 2007. I found a direct correlation between ENSO events and strandings in Florida (R2 = 0.1626) and the SEUS (R2 = 0.2236).
58

Well-being and Dispositional Optimism in Uganda and Sweden : An empirical and neurobiological investigation

Lönn, Josefina January 2015 (has links)
Uganda´s well-being ranks among the worst in the world, while Sweden´s well-being ranks among the best. This thesis investigates if there is a difference in well-being and dispositional optimism in Uganda and Sweden. The neurobiology underlying well-being and optimism is also examined. The neural correlations of well-being and optimism are connected to areas in the limbic system and cerebral cortex. Prefrontal cortex and anterior cingulate cortex are two curial regions involved in both well-being and optimism. Amygdala, parahippocampal gyrus, and thalamus are central areas for hedonic well-being, dispositional optimism, and optimism bias. In this thesis 284 Ugandans and 256 Swedes completed a questionnaire based survey. Greater hedonic well-being was found among Swedes, whereas greater eudiamonic well-being was found among Ugandans. Swedes reported greater global life satisfaction than Ugandans, but Ugandans expressed higher satisfaction with their current lives compared with Swedes. In relation to dispositional optimism, Ugandans were found to be both more optimistic and more pessimistic than Swedes. This unexpected dispositional optimism pattern is discussed and future research directions are proposed.
59

Investigating the Outcomes of Two Chronic Disease Self-Management Programs and Understanding the Correlates of Completion for Each Program

Melchior, Michael A 29 March 2012 (has links)
Chronic disease affects 80% of adults over the age of 65 and is expected to increase in prevalence. To address the burden of chronic disease, self-management programs have been developed to increase self-efficacy and improve quality of life by reducing or halting disease symptoms. Two programs that have been developed to address chronic disease are the Chronic Disease Self-Management Program (CDSMP) and Tomando Control de su Salud (TCDS). CDSMP and TCDS both focus on improving participant self-efficacy, but use different curricula, as TCDS is culturally tailored for the Hispanic population. Few studies have evaluated the effectiveness of CDSMP and TCDS when translated to community settings. In addition, little is known about the correlation between demographic, baseline health status, and psychosocial factors and completion of either CDSMP or TCDS. This study used secondary data collected by agencies of the Healthy Aging Regional Collaborative from 10/01/2008 - 12/31/2010. The aims of this study were to examine six week differences in self-efficacy, time spent performing physical activity, and social/role activity limitations, and to identify correlates of program completion using baseline demographic and psychosocial factors. To examine if differences existed a general linear model was used. Additionally, logistic regression was used to examine correlates of program completion. Study findings show that all measures showed improvement at week six. For CDSMP, self-efficacy to manage disease (p = .001), self-efficacy to manage emotions (p = .026), social/role activities limitations (p = .001), and time spent walking (p = .008) were statistically significant. For TCDS, self-efficacy to manage disease (p = .006), social/role activities limitations (p = .001), and time spent walking (p = .016) and performing other aerobic activity (p = .005) were significant. For CDSMP, no correlates predicting program completion were found to be significant. For TCDS, participants who were male (OR=2.3, 95%CI: 1.15-4.66), from Broward County (OR=2.3, 95%CI: 1.27-4.25), or living alone (OR=2.0, 95%CI: 1.29-3.08) were more likely to complete the program. CDSMP and TCDS, when implemented through a collaborative effort, can result in improvements for participants. Effective chronic disease management can improve health, quality of life, and reduce health care expenditures among older adults.
60

Vigilance behaviour and its endocrine correlates in Plains zebra (Equus burchelli) living in a predator-free landscape

Fourie, Clasina Elizabeth 17 July 2012 (has links)
Group size affects individual and collective vigilance levels of prey species. As individual vigilance decreases with increasing group size, the indirect risk of predation to each individual and the group as a whole will also decrease (dilution and many-eyes effect) which may have a decreasing effect on stress responses on group level as well. Where predation risk is low, other factors like group size might influence stress-related glucocorticoid output in prey species. I test the relationship between group size and individual and collective vigilance levels in a plains zebra (Equus burchelli) population living in an environment with low adult predation risk due to the absence of lions (Panthera leo) in the Dinokeng Game Reserve (DGR). I also test for an effect of season (wet vs. dry) on these levels. Vigilance levels are expected to be higher in summer than winter, due to a seasonal influence on susceptibility to predation or the ease of predator detection. Finally, I test if the presence of foals in a band influences individual and collective vigilance levels. Mothers are expected to increase their vigilance levels since foals are most susceptible to predation by smaller predators in the reserve. I also aimed to specifically investigate how group size affects adrenocortical endocrine activity in male and female individuals of plains zebra bands living in an environment with low predation risk. With an increase in group size, and individual vigilance expecting to decrease, the indirect risk of predation to each individual and the group as a whole will also decrease (due to both dilution and many-eyes effect) which may decrease stress on group level as well. Affiliative social interactions between females could also have the effect of improving fitness and reducing stress levels in this species. We therefore evaluated the reliability of different enzyme-immunoassays (EIA) for monitoring glucocorticoid metabolite levels in plains zebra faeces by conducting an adrenocorticotropic hormone (ACTH) challenge test and associated translocation event. Individual vigilance decreased with group size, confirming a classic group size effect; while collective vigilance remained constant meaning individuals could reduce their own scanning and rely on scanning by other group members. Individual vigilance differs between seasons, with higher levels recorded in summer, but no seasonal effect is found on rate of scanning and collective vigilance. Interestingly, bands with foals have a lower level of individual vigilance than bands without foals, which may be due to added nutritional stress on mothers during lactation. A constant collective vigilance level means mothers may be able to increase foraging time without increasing predation risk. I successfully identified two group-specific EIAs as suitable for assessing adrenocortical endocrine activity in male and female plains zebra, but gender-specific differences in response to ACTH administration and translocation were detected. In winter, bands of free-ranging plains zebra differ significantly in terms of faecal glucocorticoid metabolite (FGM) output, but due to the fact that the bands tested also differed in size as well as composition, the potential band size effect were analysed for males and females separately. Males in bands of greater size exhibit higher FGM levels than males in small bands; explained by the females’ need for protection, resource competition and reproduction pressure. FGM levels in females did not differ between bands of different sizes, indicating that potential changes in vigilance behaviour per se might not alter FGM output in a low-predation risk environment. This study confirms firstly, the classic group size effect on vigilance in plains zebra in this low predation risk environment and secondly, that group size and sex should be considered when looking at FGM levels in this social species. / Dissertation (MSc)--University of Pretoria, 2012. / Zoology and Entomology / unrestricted

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