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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.
461

The etiology of violence and the voice of the perpetrator

Schoen, JoAnna 01 January 1999 (has links)
The epidemic of violence now occurring in the United States constitutes one of the nation's most important social problems. Each year the boundaries of violence extend. Because its effects now touch all areas and populations, violence has been officially declared a major pubic health issue. The intent of this study was to explore the root causes of violence as reported by the violent offender. The study contains a review of the literature which looks at violence from a historical, biological, psychological, sociological, and psycho-social point of view. However, because the majority of research does not include direct interview or the perspective of the perpetrator, this study was designed to gather this absent information present it in their own voice. Twelve men from three different correctional facilities were interviewed. Each interview was conducted face-to-face in a private setting within the prison. Each participant was asked to talk about their life experience, history of violence, understanding of their violent activities, and finally based on their insight, offer recommendations for intervention. Additionally, they were asked to complete a powerlessness survey that queried their sense of self-esteem and self-efficacy at the time of their violent offense. In order to give the reader an opportunity to hear the voice of the participants, their stories are crafted in their own words and presented in narrative form. A number of interconnected thematic characteristics emerged from the interviews and survey. In addition to illuminating and verifying many of the speculations presented in the literature review, the findings suggest the presence of deficient, inadequate, or damaging conditions which occurred during critical developmental periods in the lives of the participants. Commonality of experience was noted within the following areas: lack of safety, lack of stable relationships, lack of education, lack of power and resources, lack of respect, lack of self-esteem, lack of self-worth, lack of self-efficacy, lack of coping skills, and lack of meaning. In this study, these deficits appear as significant predictors of eventual violent behavior. Based on the above findings, implications for clinical practice, programmatic development, and future research is suggested.
462

Comparison of language and somatic experiences between reports of trauma and trauma-related dreams & personality features of trauma-exposed persons reporting trauma-related dreams

Hickey, Kimberly Lynn 25 June 2024 (has links)
INTRODUCTION: (Study A) Trauma-Related Nightmares (TRNs) are a core feature of Post- Traumatic Stress Disorder (PTSD). We explored linguistic and somatic-experience differences between self-reports of trauma and those of nightmares related to the trauma. (Study B) Neurotic personality features are associated with many psychological disorders, including PTSD. Based on this relationship, we explored whether neuroticism predicts the rate of nightmares and bad dreams as well as the number of replicative nightmares (TRNs similar or exactly like their traumatic experience), above and beyond PTSD severity. METHODS: (Study A) Seventeen participants with varying severity of PTSD symptoms reporting recurring TRNs (mean age 27.47 years, SD = 10.33, 14 females) recalled a traumatic experience and nightmares related to that trauma. Trauma reports were written by participants, while nightmare reports were transcribed from audio recordings made as they were recalled following nightmares. Following both types of reports, participants indicated co-occurring somatic experiences by choosing from a list of 51 selections. Choices were later grouped into cardiovascular, respiratory, interoceptive, and tension categories. Linguistic content was measured using the Linguistic Inquiry and Word Count (LIWC) program and positive emotion, negative emotion, and somatosensory category words were totaled. Since trauma reports had significantly higher word counts than TRNs (p=0.0495), LIWC categories were normalized for total word count. Total and symptom- cluster severities of PTSD were assessed using the PTSD Checklist for DSM-5 (PCL-5). Wilcoxon Signed-Rank Tests and Spearman Correlations were used for statistical analysis, as Shapiro-Wilk tests showed that data were non-normally distributed. (Study B) 126 participants who had experienced a traumatic event within the past two years were recruited (mean age 24.13 years, SD = 4.994, 69% female) and, for an average of 14.89 nights, completed a dream questionnaire on which occurrence of nightmares (causing awakening) and bad dreams were reported and ranked based on their similarity to their recent traumatic experience. PTSD symptoms were assessed using the PCL-5 and personality features such as neuroticism were measured using the NEO Personality Inventory Revised (NEO PI-R), a questionnaire based on the Five Factor Model of personality. The combined number of nightmares and bad dreams was divided by the total number of nights reported and expressed as a rate, while a replicative nightmare count was generated by summing “similar to traumatic experience” and “exactly like traumatic experience” ratings. Hierarchical regressions were used to determine whether neuroticism predicted the rate of nightmare and bad dreams as well as the number of replicative nightmares above and beyond PTSD severity. Pearson correlations were used to check for relationships between variables and possible collinearity. RESULTS: (Study A) There were significantly more somatic experiences of interoception (p=0.0084) and tension (p=0.024) in trauma vs nightmare reports. The intrusion cluster of the PCL-5 was associated with cardiovascular (rho=0.592, p=0.0156) and respiratory (rho=0.619, p=0.0109) experiences in trauma reports, and interoception (rho=0.718, p=0.0033) and tension (rho=0.556, p=0.0224) experiences in nightmare reports. (Study B) In two hierarchical regression models, neuroticism predicted neither nightmare and bad dream rate nor number of replicative nightmares over and above total or PTSD symptom cluster severity (p=0.596; p=0.886). Collinearity checks did demonstrate a moderate positive relationship between these variables (r=0.317, p<0.001). CONCLUSION: (Study A) More somatic experiences of interoception and tension were recalled from traumas than TRNs. Because the brain is deafferented from sensory input during dreaming, we expected, but did not find, state differences in other somatic experiences. Word categories in narratives also did not show state differences. Only the intrusion symptoms of PTSD predicted bodily sensations in trauma as well as TRN reports. (Study B) We found that neuroticism did not predict either nightmare and bad dream rate or the number of replicative nightmares above and beyond PTSD severity, when taking demographic factors into account. The positive correlation between PTSD and neuroticism could explain this lack of significance. SUPPORT: R21MH128619
463

Effects of Emotion on Memory Formation and Storage

Jones, Diane R. 21 April 2005 (has links)
No description available.
464

The role of mGluR5 during conditioned hyperactivity and sensitization in differentially reared rats

Gill, Margaret J. January 1900 (has links)
Doctor of Philosophy / Department of Psychology / Mary E. Cain / Glutamate contributes to the neurological and behavioral changes that occur during differential rearing, and those that occur during conditioned hyperactivity and sensitization. Metabotropic glutamate receptor 5 (mGluR5) in particular contributes to the psychostimulant reward pathway, plasticity, and differential rearing. The present study examined the role of mGluR5 in conditioning and sensitization in differentially reared rats. Rats were reared in an enriched (EC), impoverished (IC), or social (SC) condition for 30 days, after which they received repeated amphetamine (0.3 mg/kg) or saline injections. Following training, rats received an injection of the mGluR5 antagonist MTEP or saline prior to undergoing conditioned hyperactivity and sensitization tests. Results showed that MTEP attenuated conditioned hyperactivity and sensitization in IC but not EC and SC rats, suggesting that glutamatergic changes occur during differential rearing that alter the effects of MTEP on amphetamine conditioning and sensitization. Additionally, results demonstrated that enrichment rearing has a protective effect against conditioned hyperactivity at low doses of amphetamine.
465

Effects of differential rearing on amphetamine-induced c-fos expression in rats

Gill, Margaret J. January 1900 (has links)
Master of Science / Department of Psychology / Mary E. Cain / Previous research has shown that both the environment and psychostimulant use influence dopamine levels via the mesolimbic dopamine pathway. C-fos expression has also been observed following exposure to novel environments and psychostimulants. The present study looked to determine the effects of acute amphetamine exposure on locomotor activity and c-fos expression in the basolateral and central nucleus of the amygdala, for rats raised in either an enriched condition (EC), impoverished condition (IC), or social condition (SC). Rats were reared in either the EC, IC, or SC for 30 days, after which they received an acute amphetamine injection (1.0 mg/kg) and locomotor activity was measured. Following the locomotor test rats were perfused and immunohistochemistry was used to measure c-fos levels in the basolateral and central nucleus of the amygdala. Results showed that EC amphetamine rats had significantly greater locomotor activity compared to EC saline rats. There were no significant group or treatment differences in c-fos expression in the ACe. In the BLA SC amphetamine rats had significantly greater c-fos expression than EC amphetamine rats. Overall, the current study revealed that environmental enrichment and amphetamine do significantly alter locomotor activity and c-fos expression in the BLA.
466

Presence of menarche is associated with high depressive symptoms and cortisol levels in adolescent girls

Trepanier, Lyane 08 1900 (has links)
Plusieurs études antérieures ont proposé que la ménarche pouvait représenter une vulnérabilité accrue au développement de la dépression en augmentant la réactivité au stress chez les filles ayant atteint leur cycle menstruel. Dans la présente étude, les symptômes dépressifs et les niveaux de cortisol salivaire ont été mesurés chez 198 garçons et 142 filles (11 - 13 ans), et ce, à quatre reprises au cours de leur première année de transition vers l’école secondaire, une période de stress chez les adolescents. Les résultats ont montré que les filles qui avaient atteint la ménarche au moment de la transition vers le secondaire avait des niveaux significativement plus élevés de symptômes dépressifs et de cortisol salivaire entre l’automne et le printemps, comparativement aux filles qui n'avaient pas encore atteint la ménarche. Ces dernières présentaient des niveaux plus élevés de symptômes dépressifs que les filles sans et les garçons. Les filles sans ménarche présentaient d’avantages des niveaux de symptômes dépressives plus élevés que les garçons. En utilisant l’âge de ménarche comme variable catégorique, les résultats démontrent que les filles ayant eu leur ménarche plus jeunes présentent des symptômes dépressifs plus élevés tout au long de l'année scolaire, alors que les filles qui ont commencé leur cycle menstruel à l’âge dit ‘normal’ présentent des symptômes dépressifs transitoires. Globalement, ces résultats suggèrent que la ménarche est un indice significatif d’une vulnérabilité accrue pour les symptômes dépressifs et les niveaux de cortisol plus élevés chez les adolescentes qui font leur entrée au secondaire. Également, ces résultats suggèrent qu’un âge précoce de ménarche peut exposer à long-terme le cerveau en développement à des niveaux élévés de cortisol, rendant ainsi ce groupe d’adolescentes plus vulnérables à la dépression. / It has been proposed that the onset and/or earlier age at menarche confer greater vulnerability to depressive symptoms by increasing the reactivity of menarcheal girls to stressors associated with adolescence. In the present study, we measured depressive symptoms and salivary cortisol levels in 198 boys and 142 girls (11 -13 years) tested four times during their first year of transition into high school, a period known to be associated with stress among adolescents. Results showed that girls who had reached menarche before the transition to high school transit presented significantly higher depressive symptoms and salivary cortisol levels across the school year, when compared to girls who had not reached menarche and boys. Girls who had reached menarche presented significantly higher depressive scores than girls who had not reached menarche and boys. Girls who did had not reached menarche also scored significantly higher on depressive symptoms when compared to boys. When we divided the menarcheal girls as a function of age of onset, we found that girls with early age at menarche presented consistently higher scores for depressive symptoms from the start of the school year to early spring. Girls with on-time menarche scored higher for symptoms of depression, but these were more transitory. Altogether, these results show that onset of menarche is associated with greater depressive symptoms and higher cortisol levels in adolescent girls going through the stress of high school transition. These findings also suggest that early menarche may confer greater vulnerability to depression due to long-term exposure of the developing brain to high cortisol levels.
467

L'impact des résections de l'insula sur la personnalité

Hebert-Seropian, Benjamin 08 1900 (has links)
La recherche montre que l’insula est impliquée dans le traitement d’informations intéroceptives, émotionnelles et relevant de fonctions exécutives de haut niveau. L’hypothèse des marqueurs somatiques propose que ces fonctions vraisemblablement séparées travaillent plutôt de concert au sein d’un système neural dont le rôle consiste à extraire les messages émotionnels des signaux corporels. Si l’insula exerce effectivement un rôle de modulateur des sensations corporelles et des processus cognitifs découlant de ceux-ci, des lésions au cortex insulaire risquent d’occasionner des altérations au niveau de l’expérience émotionnelle, des fonctions exécutives et de la personnalité. La présente étude a pour but de mesurer ces changements chez 19 patients ayant subi une insulectomie unilatérale dans le cadre de leur traitement de l’épilepsie. Ces patients ont été comparés à un groupe contrôle composé de 19 patients épileptiques ayant subi une résection du lobe temporal. Les participants ont été évalués par l’entremise du Iowa Scales of Personality Change (ISPC), rempli par un proche du patient. Les résultats montrent que les patients du groupe insulaire exhibent des changements qui dénotent une dérégulation émotionnelle à long terme, caractérisée par une augmentation modérée de l’irritabilité, de la labilité émotionnelle, de l’anxiété et de la frugalité, tous des changements qui, outre l’anxiété, n’ont pas été observés chez les patients temporaux. Cependant, pour ce qui est des fonctions exécutives, aucun changement significatif n’a été noté. De plus, la comparaison pré- et post opératoire des scores des deux groupes aux items de l’ISPC ne s’est pas avérée significative. Globalement, les résultats suggèrent que l’insula joue probablement un rôle accessoire au sein du modèle proposé par l’hypothèse des marqueurs somatiques et que les résections unilatérales partielles ou complètes de l’insula ne risquent pas d’occasionner de changements prononcés de la personnalité. / Research has shown that the insula is involved in the processing of information relating to interoceptive, emotional and executive functions. It was proposed that these two seemingly separate functions may work conjointly as part of a large neural circuit tasked with the extraction of emotional information from bodily signals. It was hypothesized that, if the insula does indeed modulate feelings and the cognitive processes which derive from them, insular damage would result in alterations of emotional experience, executive functions and personality. To that effect, we examined such changes in a group of patients (n = 19) who underwent epilepsy surgery involving partial or complete resection of the insula, and compared them to a group of patients who underwent temporal lobe epilepsy surgery (n = 19) as a lesion-control group. Participants were assessed on the Iowa Scales of Personality Change, filled by a close relative at least six months after surgery. While pre- vs. post-surgery changes did not significantly differ between groups on any of the outcome variables, insular resections were associated with mild but significant increases in irritability, emotional lability, anxiety, and frugality postoperatively, which, with the exception of increased anxiety, were not found among temporal patients. Against our initial prediction, the surgery did not lead to executive functioning deficits. Overall, our results support the notion that the insula most likely holds an accessorial role in the model proposed by the somatic marker hypothesis, and that there isn’t a risk of dramatic personality change as a result of the partial or complete unilateral surgical removal of the insula.
468

Le rôle de la sérotonine sur le développement de traits anxieux : une étude de trajectoire longitudinale

Farshadgohar, Tina 11 1900 (has links)
Certains gènes, modulant la sérotonine (5-hydroxytryptamine, 5-HT), ont été associés aux tempéraments liés à l'anxiété. Une limitation dans la plupart de ces études est que les études sont de nature transversale et l'anxiété a été évaluée à un seul point dans le temps. De plus, seules quelques études ont été réalisées chez les enfants. Le but de la présente étude était d'étudier le rôle des gènes HTR2A et TPH2 dans le développement des trajectoires d’anxiété durant l’enfance. Les associations entre ces gènes, ces trajectoires, le diagnostic d’anxiété à l'âge adulte et les différences entre les sexes ont été examinées dans l'Étude Longitudinale des Enfants de Maternelle au Québec, composée de 3185 enfants recrutés en 1986-1987. Leur anxiété a été cotée par leur professeur annuellement entre 6 et 12 ans. Ces cotes ont été modélisées en trajectoires comportementales. Les données genotypées de 5-HT, disponibles pour 1068 personnes, ont été analysées en utilisant les statistiques du Chi-carré, des régressions logistiques et des analyses de variance. Sur les 37 polymorphismes étudiés, plusieurs ont été associés à la trajectoire de forte anxiété, tels le 5-HTR2A (rs1328684, rs95534511, rs1745837, rs7984966, 7330636) et TPH2 (rs11179050, rs11179052, rs1386498). Bien que les trajectoires d’anxiété en enfance n’aient pas prédit le diagnostic d'anxiété à 21 ans, les relations ont été trouvées entre ce diagnostic, HTR2A et les polymorphismes du nucléotide simple (PNS) de TPH2. On remarque que les PNS associés à l’anxiété durant l’enfance et l’âge adulte ne sont pas les mêmes. La force d'association entre les gènes étudiés et l'anxiété diffère entre les garçons et les filles. Cette étude est la première à identifier une association entre les variantes TPH2, 5-HTR2A et les trajectoires d’anxiété en enfance. Les études futures devraient reproduire les résultats dans d'autres échantillons, enquêter sur l'interaction avec les facteurs de stress, et étudier la pertinence fonctionnelle de la PNS. / A number of genes known to modulate serotonin (5-hydroxytryptamine, 5-HT) have been associated with anxiety-related temperaments. A limitation in most of these studies is that the studies are cross-sectional and anxiety has been measured at a single point in time. Furthermore, only a few studies have been done in children. The aim of the present study was to investigate the role of the HTR2A and TPH2 gene in the development of trajectories of anxiety in childhood/ adolescence. Associations between these genes, anxiety trajectories in childhood and anxiety diagnoses in adulthood were also investigated. Finally, gender differences were explored. Research questions were investigated in the Quebec Longitudinal Study of Kindergarten Children, consisting of 3185 boys and girls, selected in 1986-1987. Children`s anxiety was rated by their teacher every year between the age of 6 and 12 years. The ratings were modeled into behavioral trajectories. 5-HT genotyping data were available for 1068 cohort members. Data were analyzed using Chi-square statistics, logistic regressions and ANOVAs. Out of 37 investigated polymorphisms, several polymorphisms, such as 5-HTR2A (rs1328684, rs95534511, rs1745837, rs7984966, 7330636) and TPH2 (rs11179050, rs11179052, rs1386498) were associated with a high anxiety trajectory. Though trajectories of high anxiety in childhood did not predict an anxiety diagnosis at age 21, relationships were found between HTR2A and TPH2 SNPs and anxiety diagnosis at age 21. We note that the SNPs associated with anxiety were different between adults and children. The strength of association between the investigated genes and anxiety differed between boys and girls. This is the first study reporting an association with some HTR2A and TPH2 variants and trajectories of anxiety in children. Future studies should replicate the findings in other samples, investigate the interaction with stressors, and study the functional relevance of the SNPs
469

Attentional Biases in Value-Based Decision-Making

San Martin Ulloa, Rene January 2014 (has links)
<p>Humans make decisions in highly complex physical, economic and social environments. In order to adaptively choose, the human brain has to learn about- and attend to- sensory cues that provide information about the potential outcome of different courses of action. Here I present three event-related potential (ERP) studies, in which I evaluated the role of the interactions between attention and reward learning in economic decision-making. I focused my analyses on three ERP components (Chap. 1): (1) the N2pc, an early lateralized ERP response reflecting the lateralized focus of visual; (2) the feedback-related negativity (FRN), which reflects the process by which the brain extracts utility from feedback; and (3) the P300 (P3), which reflects the amount of attention devoted to feedback-processing. I found that learned stimulus-reward associations can influence the rapid allocation of attention (N2pc) towards outcome-predicting cues, and that differences in this attention allocation process are associated with individual differences in economic decision performance (Chap. 2). Such individual differences were also linked to differences in neural responses reflecting the amount of attention devoted to processing monetary outcomes (P3) (Chap. 3). Finally, the relative amount of attention devoted to processing rewards for oneself versus others (as reflected by the P3) predicted both charitable giving and self-reported engagement in real-life altruistic behaviors across individuals (Chap. 4). Overall, these findings indicate that attention and reward processing interact and can influence each other in the brain. Moreover, they indicate that individual differences in economic choice behavior are associated both with biases in the manner in which attention is drawn towards sensory cues that inform subsequent choices, and with biases in the way that attention is allocated to learn from the outcomes of recent choices.</p> / Dissertation
470

Kangaroo care with full-term infants: maternal behaviors and mother-infant bonding

Unknown Date (has links)
Kangaroo care (KC), has been shown to promote healthy development for both pre-term and full-term infants, and to improve mother-infant bonding (Ludington-Hoe, 2011; Charpak et al., 2005). Current research on the maternal benefits of kangaroo care is scarce, primarily focuses on early KC, and is mostly qualitative in nature (Fegran, Helseth, & Fagermoan, 2008; Matos et al., 2010). The present study examined the effect of late KC on maternal behaviors, sensitivity, and mother-infant interactive mutuality when infants were 3 months of age. Mothers who used kangaroo care as directed were found to have greater bonding scores and less anxiety about caring for their infants as measured through the Postpartum Bonding Questionnaire. Kangaroo care was also found to have an effect on mothers’ ability to effectively calm their infants after an arm restraint task. Further research on the usefulness of late intermittent KC with full-term infants is needed. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

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