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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.
131

O rebaixamento da negatividade da arte: Um estudo sobre a instrumentalização do teatro na educação / The lowering of the negativity of art: a study of transforming theater into an instrument of education

Yonara Dantas de Oliveira 03 May 2010 (has links)
Este estudo discute a inserção do teatro no âmbito educacional, considerando o atravessamento do teatro pela instituição escolar e os movimentos que permearam a história do teatro. Com base na teoria crítica da sociedade desenvolvida por Theodor Wiesengrund Adorno, entende-se que o teatro, como expressão artística, é, em si, forma de conhecimento. Por meio do seu caráter de negatividade, as obras de arte condensam as antinomias e os antagonismos como antíteses da sociedade enquanto problema de sua forma interna, o que potencializa a arte como crítica imanente à realidade social. Partindo desse entendimento, buscou-se elucidar como o teatro se relaciona com os demais conteúdos escolares. Para tanto, foram selecionadas como material para análise quatro produções acadêmicas sobre teatro e educação, entre dissertações e teses produzidas na Universidade de São Paulo, já situadas dentro do contexto da vigência da nova Lei de Diretrizes e Bases da Educação, de 1996, e da implementação dos Parâmetros Curriculares Nacionais, em 1998. As reflexões de Theodor W. Adorno e as discussões apresentadas nas obras selecionadas contribuem para a compreensão do objeto de estudo, em uma análise sobre a relação entre teatro e educação escolar, a qual indaga de que maneira, nessa relação, o teatro encontra-se rebaixado em seu potencial de contato com a realidade e de crítica a ela. Da análise das quatro obras selecionadas é possível depreender que o teatro encontra-se instrumentalizado, tendo em vista que as atividades de ensino de teatro têm ido ao encontro de uma educação afirmativa da ordem vigente / This study is about the insertion of theater in the educational field, and it considers the crossing through of theater by the school, as well as the movements that permeate the history of theater. Based on the critical theory of society developed by Theodor Wiesengrund Adorno, it is understood that theater itself, as an artistic expression, is a way of knowledge. The works of art condense both the contradictions and the antagonism as antitheses of society as problems of their inner shape through their character of negativity, which reinforces art as criticism pertaining to the social reality. From that perception, it was explained how theater relates to the other school contents. To do so, four academic papers about theater and education were selected among the theses and dissertations done at Universidade de São Paulo after the new National Education Bases and Guidelines Law was in force (the law has been ruling since 1996) and the National Curriculum Parameters were implemented (1998). Both Theodor W. Adorno´s thoughts and the discussions in the selected papers help to understand the object of the present study, in an analysis of the relation of theater to education, which searches the way theater is lowered in its potential of contact with reality and criticism of it inside such relation. From the analyses of the four selected papers it is possible to infer that theater has been transformed into an instrument of education, for the teaching activities of theater have met the education of the ruling order
132

Is the High Probability of Type II Error an Issue in Error Awareness ERP Studies?

Dalile, Boushra January 2016 (has links)
When researchers began addressing the electrophysiology of conscious error awareness more than a decade ago, the role of the error-related negativity (ERN), alongside the subsequently occurring error positivity (Pe), was an obvious locus of attention given the fact that they are taken as indices of cortical error processing. In contrast to the clear-cut findings that link the amplitude of the Pe to error awareness, the association between the ERN amplitude and error awareness is vastly unclear, with a range of studies reporting significant differences in the ERN amplitude with respect to error awareness, while others observing no modulation of the ERN amplitude. One problem in the studies obtaining null findings is the fact that conclusions are drawn based on small sample sizes, increasing the probability of type II error, especially given the fact that the ERN elicited using various error awareness paradigms tends to be small. The aim of the present study was to therefore address the issue of type II error in order to draw more certain conclusions about the modulation of the ERN amplitude by conscious error awareness. Forty participants performed a manual response inhibition task optimised to examine error awareness. While the early and late Pe amplitudes showed the expected sensitivity to error awareness, the ERN results depicted a more complex picture. The ERN amplitude for unaware errors appeared more negative than that of aware errors, both numerically and on the grand average ERP. The unexpected findings were explained in terms of (a) latency issues in the present data, (b) characteristics of the manual response inhibition task used and the possibility that it elicits variation in neurocognitive processing, and (c), in relation to possible contamination by the contingent negative variation (CNV), an ERP component elicited during response preparation. Suggestions for future research on how to address the issues raised in the present paper are also discussed.
133

Biomass conversion through syngas-based biorefineries : thermochemical process integration opportunities

Åberg, Katarina January 2017 (has links)
The replacement of fossil resources through renewable alternatives is one way to mitigate global climate change. Biomass is the only renewable source of carbon available for replacing oil as a refining feedstock. Therefore, it needs to be utilized not just as a fuel but for both biochemical and thermochemical conversion through biorefining. Optimizing and combining various conversion processes using a system perspective to maximize the valorization, biomass usage, and environmental benefits is of importance. This thesis work has evaluated the integration opportunities for various thermochemical conversion processes within a biorefinery system. The aim for all evaluated concepts were syngas production through gasification or reforming. Two potential residue streams from an existing biorefinery were evaluated as gasification feedstocks, thereby combining biochemical and thermochemical conversion. Torrefaction as a biomass pretreatment for gasification end-use was evaluated based on improved feedstock characteristics, process benefits, and integration aspects. A system concept, “Bio2Fuels”, was suggested and evaluated for low-temperature slow pyrolysis as a way to achieve simultaneous biomass refinement and transport driven CO2 negativity. Syngas was identified as a very suitable intermediate product for residue streams from biochemical conversion. Resulting syngas composition and quality showed hydrolysis residue as suitable gasification feedstock, providing some adjustments in the feedstock preparation. Gasification combined with torrefaction pretreatment demonstrated reduced syngas tar content. The co-gasification of biogas and wood in a FBG was successfully demonstrated with increased syngas H2/CO ratio compared to wood gasification, however high temperatures (≥1000°C) were required for efficient CH4 conversion. The demonstrated improved feedstock characteristics for torrefied biomass may facilitate gasification of biomass residue feedstocks in a biorefinery. Also, integration of a torrefaction unit on-site at the biorefinery or off-site with other industries could make use of excess low-value heat for the drying step with improved overall thermal efficiency. The Bio2Fuels concept provides a new application for slow pyrolysis. The experimental evaluation demonstrated significant hydrogen and carbon separation, and no significant volatilization of ash-forming elements (S and Cl excluded)  in low-temperature (<400°C) pyrolysis. The initial reforming test showed high syngas CH4 content, indicating the need for catalytic reforming. The collective results from the present work indicate that the application of thermochemical conversion processes into a biorefinery system, making use of by-products from biochemical conversion and biomass residues as feedstocks, has significant potential for energy integration, increased product output, and climate change mitigation.
134

Le pouvoir entre négativité et productivité : le thème de l'exclusion dans la pensée foucaldienne / Power : between negativity and productivity : the theme of exclusion in Foucault's thinking

Goloborodko, Denis 21 October 2016 (has links)
La problématique du pouvoir est tout à fait centrale dans l'œuvre de Michel Foucault et les études foucaldiennes à ce sujet n'ont pas manqué. Pourtant il nous semble nécessaire de rendre mieux visible le mouvement d'ensemble et l'intention générale de Foucault : moins une critique du pouvoir qu'une reconsidération de la nature du pouvoir, qui le détache de tout sujet identifiable. Dans cette perspective, parmi les moments les plus généraux de la pensée foucaldienne du pouvoir, c'est avant tout la description du pouvoir en termes d'inclusion et d'exclusion qui a paru la plus prometteuse dans l'optique d'une analyse philosophique. Ce sont les deux fonctions principales du pouvoir, mais tout en étant terminologiquement antagonistes, elles ne rentrent néanmoins pas en opposition. Au sein de ce que Foucault appelle les «relations de pouvoir», ces deux fonctions agissent simultanément, l'une se cachant pendant que l'autre s'expose. L'analyse de ces fonctions du pouvoir permet d'appréhender les trois formes de pouvoir chez Foucault (souveraineté, discipline, bio-pouvoir) et de dégager dans les évolutions qui conduisent de l'une à l'autre une « productivité » du pouvoir, opposée à l'idée de « négativité » du pouvoir. / The issue of power is absolutely central in the work of Michel Foucault, and it has been widely studied. Nevertheless, it was necessary to further show the overall movement and intention of Foucault on this matter: less of a criticism to power than a rethinking of the nature of power that detaches it from any identifiable object. In this context, among the general outlines of Foucault's thinking of power, the description of power in terms of inclusion and exclusion seems to be the most promising from a philosophical perspective. These are the two functions of power, but despite of being terminologically conflicting, they do not oppose each other. Within what Foucault describes as the “relations of power”, these two functions act simultaneous, each hiding when the other shows. The analysis of the functions of power allows to understand the three forms of power of Foucault (sovereign power, disciplinary power, and biopower) and to identify – in the evolutions that lead from one to another – a ''productivity'' of power, in opposition to the idea of the “negativity” of power.
135

Recherche de signes de conscience chez des malades non communicants : une approche clinique et électrophysiologique / Awareness assessment in disorders of consciousness patients : a clinical and electrophysiological approach

Faugeras, Frédéric 12 September 2014 (has links)
Comprendre les mécanismes neurophysiologiques et les bases neurales de la conscience est un défi médico-scientifique majeur. A cette fin, il faut opérer une distinction entre les mécanismes neuraux des états de conscience, et ceux qui sous-tendent l'accès conscient à un contenu mental particulier (ou la prise de conscience). Les données expérimentales ayant contrasté état conscient/ état non conscient (coma, sommeil, sédation) d'une part, et perception consciente/inconsciente d'un même stimulus d'autre part, sont en faveur de l'implication d'un réseau d'aires cérébrales fronto-pariétales à la fois dans l'état et dans l'accès conscient à une information donnée. La comparaison état conscient/ état non conscient est malheureusement limitée par les différences de vigilance existant entre ces états. Nous avons cherché à contourner ce problème en nous focalisant sur deux populations de malades présentant un niveau de vigilance proche mais différant sous l'angle de l'état de conscience : patients éveillés, non conscients (état végétatif) versus patients éveillés et minimalement conscients (état de conscience minimale). Nos résultats, obtenus en utilisant les potentiels évoqués auditifs cognitifs à haute densité spatiale, sont en faveur de l'implication du même réseau d'aires cérébrales fronto-pariétales que celui mentionné ci-dessus, à la fois dans l'état et l'accès conscient. L'activation de ce réseau est contemporaine de l'apparition d'une P300b en potentiels évoqués qui semble constituer un marqueur très spécifique de conscience. Notre travail nous a permis également d'identifier un possible nouveau marqueur de la conscience qu'est la variation contingente négative (CNV). / Understanding the neurophysiological mechanisms and neural bases of consciousness is a major scientific and medical challenge. To do this, one has to distinguish neural mechanisms of conscious state from those subserving conscious access to a given mental state (that is awareness). Experimental data having contrasted conscious / non conscious state (coma, sleep, sedation) on the one hand, and conscious/ unconscious processing of a very same stimulus on the other hand are in favour of the implication of a network of lateral and medial frontal and parietal areas in both conscious state and conscious access. The comparison of conscious/ non conscious state is unfortunately limited by arousal difference between these two states. So, we endeavoured to overcome this problem by exploring two categories of patients with a same level of arousal but a different state of awareness: unaware awaked patients (vegetative state) versus awaked and minimally conscious patients (minimally conscious state). Our results obtained by using high-density auditory event related potentials argue in favour of the implication of the very same network of frontal and parietal areas than the one described above in both conscious state and conscious access to a given information. This network activation is associated with the emergence of a P300b wave, on event related potentials, which seems to be a very specific marker of consciousness. Our work also give us the opportunity to discover a potential new marker of consciousness, namely the contingent negative variation (CNV).
136

Influence de l'apprentissage musical sur le traitement des syllabes chez des enfants normolecteurs et dyslexiques

Chobert, Julie 29 June 2011 (has links)
Mon thème de recherche est d’étudier l’influence de l’apprentissage de la musique sur le traitement acoustique et phonologique de la syllabe chez des enfants normolecteurs et dyslexiques. Dans ce but, j’ai conduit plusieurs expériences basées sur l’utilisation conjointe des méthodes issues de la psychologie expérimentale (Temps de Réaction, TRs, et pourcentage d’erreurs, %err) et de l’électrophysiologie chez l’homme (Potentiels Evoqués, PEs). En comparant des enfants musiciens et non-musiciens de 9 ans, j’ai d’abord testé les effets de l’expertise musicale sur les traitements attentif (TRs et %err) et pré-attentif (en utilisant la Mismatch Negativity, MMN) de paramètres acoustiques, fréquence et durée des syllabes, et d’un paramètre phonologique, le Voice Onset Time (VOT; Expérience I). Les résultats montrent que l'expertise musicale améliore les traitements pré-attentif et attentif de la durée et du VOT dans les syllabes et le traitement attentif des variations de fréquence. Dans une seconde étude, j’ai utilisé la MMN pour comparer le traitement de ces mêmes paramètres chez des enfants dyslexiques et normolecteurs. Les enfants dyslexiques montrent un déficit du traitement de la durée des syllabes et du VOT comparés aux enfants normolecteurs. Enfin, dans les deux dernières études, j’ai utilisé la méthode longitudinale pour tester l’influence de l’apprentissage de la musique sur le traitement pré-attentif (MMN) de ces mêmes paramètres chez des enfants normolecteurs (Expérience III) et dyslexiques (Expérience IV). Les résultats de l’Expérience III montrent que 12 mois d’apprentissage de la musique améliorent le traitement pré-attentif de la durée et du VOT chez les enfants normolecteurs. En reproduisant les effets trouvés dans l’Expérience I, ces résultats soulignent que l’avantage mis en évidence chez les enfants musiciens ne résulterait pas uniquement de prédispositions génétiques pour la musique mais serait causalement lié à l’apprentissage musical. Enfin, les résultats de l’Expérience IV montrent que 6 mois d’apprentissage de la musique améliorent le traitement pré-attentif du VOT chez les enfants dyslexiques, suggérant que l’apprentissage musical pourrait être utilisé comme une aide à la remédiation de la dyslexie.Pris dans leur ensemble, ces résultats démontrent une relation forte entre traitements acoustique et phonologique. L’apprentissage de la musique, en améliorant la sensibilité des enfants aux paramètres acoustiques dans la musique et dans le langage (processus communs), augmenterait également leur sensibilité aux paramètres phonologiques associés et permettrait ainsi la construction de représentations phonologiques plus robustes (transfert d’apprentissage de la musique vers le langage). / My research is aimed at studying the influence of musical training on the acoustic and phonological processing of syllables in children with dyslexia and in normal-reading children. To this aim, I conducted several experiments by using methods issued from experimental psychology (Reaction Times, RTs, and error rates, %err) and from human electrophysiology (Event-Related brain Potentials, ERPs)By comparing 9-year-old musician and non-musician children, I first tested for the effects of musical expertise on attentive (RTs and %err) and preattentive processing (by using the Mismatch Negativity, MMN) of the acoustical parameters, frequency and duration, of syllables and of a phonological parameter, the Voice Onset Time (VOT; Experiment I). Results showed enhanced preattentive and attentive processing of syllables’ duration and VOT in musicians compared to nonmusician children. Secondly, I compared the processing of these same parameters in dyslexic and normal-reading children (Experiment II) by using the MMN. Results revealed that children with dyslexia showed deficits for the processing of duration and VOT in syllables compared to normal-readers. Finally, in the last two studies, I used the longitudinal method to test for the influence of musical training on the processing of the same acoustic and phonological parameters of syllables, in normal-reading children (Experiment III) and in children with dyslexia (Experiment IV). Results of Experiment III showed that 12 months of musical training enhanced duration and VOT processing in syllables, thereby demonstrating that the effects of musical expertise shown in Experiment I are not likely to only result from specific genetic predispositions for music but are causally linked to musical training. Finally, results of Experiment IV revealed that 6 months of musical training in children with dyslexia enhanced their sensitivity to VOT processing, suggesting that musical training could be an aid for the remediation of dyslexia.These results highlight the relationship between acoustical and phonological processing. Musical training, by refining the acoustical network responsible for the acoustic processing in music and speech sounds (common processing) also enhances sensitivity to phonological associated features and, consequently, the building-up of more robust phonological representations (transfer of training effect from music to language processing).
137

Réflexions sur la mort en tant qu'expérience de la négativité autour de Jacques Lacan et Hegel / Reflexiones sobre la muerte en tanto experiencia de la negatividad alrededor de Jacques Lacan y Helgel

Souyris Oportot, Lorena 15 December 2014 (has links)
Bien que le thème de la pulsion de mort soit souvent perçu à travers un processus biologique de destruction ou de régression à un état de nirvana comme l’affirme Freud, il est cependant utilisé ici sous une perspective spéculative pour penser son statut en s’inscrivant dans les réflexions qui prendraient part à une confrontation, et dans le même temps, une articulation entre Jacques Lacan et Hegel. De sorte que la mort, à travers la détermination ontologique permet d’ouvrir la voie pour étudier la psychanalyse à la frontière de l’être et du penser, non seulement dans sa dialectique avec le sujet et le signifiant, mais également dans son appartenance, par le sujet et sa pensée à son rapport ineffaçable avec l’impensé, ce qui conduit à la constitution de la dépossession, la perte et la destitution de l’identification du Moi spéculaire.Dans cette perspective, le concept de dialectique constitue le point de départ méthodologique pour réfléchir sur le thème de la mort à partir de son statut logique/ontologique et de son déroulement signifiant soutenu par un “examen” sceptique en tant que moment essentiel de le traitement psychanalytique, conduisant ainsi à rendre compte de la subjectivité et de sa brèche/ faille constitutionnelle comme une menace, toujours présente, de désintégration et de négativité.Quant au scepticisme, il est un autre point de départ à cette réflexion et l’origine d’un déplacement vers un regard de la psychanalyse qui va au-delà du domaine clinique. En partant de la fonction de la négation, qui semble s’inscrire comme énonciation sceptique, et à partir de questions à propos de la dissolution, la disparition ou particulièrement, l’abolition [l’aufhebung] du sujet comme lieu impossible dans sa subjectivité en manque, dont l’expression psychique est en concordance avec la déchirure interne que représente le clivage, manifestée à travers le sujet barré, ce travail considère la possibilité d’un regard ontologique de la psychanalyse. Celui-ci supposerait la mort comme ce qui instaure une expérience scripturaire de négativité et qui va jusqu’à désigner l’espace spécifique de l’activité sceptique comme examen qui dirige l’aspect tragique dans le traitement psy / The theme of the pulsion of death is, sometimes, understood in the light of a biologic principle of destruction or regression to a state of nirvana as stated by Freud, nonetheless, here it is mobilized in a speculative perspective to think its status by inscribing the reflections that would take place in a confrontation and, at the same time, articulation between Jacques Lacan and Hegel. Thus, death, under the ontological determination, allows to open the way to study psychoanalysis at the border between the being and the thinking, not only in its dialectics with the subject and the signifier but also in its belonging, by the subject and his thought, to his/her indelible relation to the unthought which involves the formation of dispossession, loss and removal of the identification of the mirrored self. From this perspective, the concept of dialectics constitutes the methodological starting point to reflect about the theme of death from their logical/ontological status and its significant development mantained by a skeptical “exam” as an essential moment in the psychoanalytic cure, involving the realisation of the subjectivity and its constitutional gap/failure as an ever-present threat of disintegration and negativity.As far as it is concerned, skepticism is another starting point of this reflection and the origin of a shift towards a view of psychoanalysis that goes beyond the clinic. As of the role of negation, which we believe it is inscribed as a skeptical utterance, as well as questions about the dissolution, disappearance or specifically abolition [l'Aufhebung] of the subject as an impossible place in his/her missing subjectivity whose psychic expression is in agreement with the internal tear that means split, manifested through the barred subject. This paper considers the possibility of an ontological view of psychoanalysis that would suppose the death as that that institutes a scripturaire experience of negativity and that even designates the specific space of the skeptical activity as an examination that directs the tragic aspect of the psychoanalytic cure.But, how does this displacement of a psychoanalytic clinic operate towards an ontology of psychoanalysis? What is at stake in the movement of the signifying chain inasmuch so a dialectical process that "remains" and that "opposes/sursumée"? To what extent does skepticism appear as a suitable tool for the "exam" and a particular interpretation not just of the unconscious but, also, of the personal history of the subject in its aspect of their subjectivity dislocated? / El tema de la pulsión de muerte siendo, a menudo, entendido a la luz de un principio biológico de destrucción o regresión a un estado de nirvana tal y como lo afirma Freud, sin embargo, aquí es movilizada en una perspectiva especulativa para pensar su estatuto inscribiéndose en las reflexiones que tomarían partida en una confrontación y, al mismo tiempo, articulación entre Jacques Lacan y Hegel. De suerte que la muerte, bajo la determinación ontológica, permite abrir la vía para estudiar el psicoanálisis en las fronteras entre el ser y el pensar, no solo en su dialéctica con el sujeto y el significante sino también en su pertenencia, por parte del sujeto y su pensamiento, a su relación imborrable con lo impensado lo que conlleva la constitución de la desposesión, la perdida y destitución de la identificación del Yo especular. Desde esta perspectiva, el concepto de dialéctica constituye el punto de inicio metodológico para reflexionar el tema de la muerte a partir de su estatuto lógico/ontológico y su desenvolvimiento significante sostenido por un “examen” escéptico en cuanto momento esencial en la cura psicoanalítica, conllevando así a dar cuenta de la subjetividad y su brecha/falla constitucional como una amenaza siempre presente de desintegración y negatividad. Por su parte, el escepticismo es otro punto de partida de esta reflexión y el origen de un desplazamiento hacia una mirada del psicoanálisis que va mas allá de lo clínico. Partiendo de la función de la negación, que a nuestro parecer se inscribe como enunciación escéptica, así como también de preguntas acerca de la disolución, la desaparición o específicamente la abolición [l’aufhebung] del sujeto como lugar imposible en su subjetividad en falta cuya expresión psíquica esta en concordancia con el desgarro interno que significa la escisión, manifestada a través del sujeto barrado, este trabajo considera la posibilidad de una mirada ontológica del psicoanálisis que supondría la muerte como aquello que instituye una experiencia scripturaire de negatividad y que hasta designa el espacio específico de la actividad escéptica como examen que dirige el aspecto trágico en la cura psicoanalítica. Pero, como se opera este desplazamiento de una clínica psicoanalítica hacia una ontología del psicoanálisis? Qué es lo que está en juego en el movimiento de la cadena significante en cuanto un proceso dialectico que « permanece » y que se « opone/sursumée » ? En qué medida el escepticismo aparece como una herramienta apropiada para el “examen” y una interpretación particular no solo del inconsciente sino, también, de la historia personal del sujeto en su aspecto de su subjetividad dislocada?Apoyándonos en algunos elementos del pensamiento Hegeliano como las determinaciones-de-reflexión, la lógica de la Esencia, la diferencia y la contradicción y, en particular, sobre los textos de Lacan relacionado con el goce, la falta y el Otro esta investigación interroga la lógica/ontológica de la muerte para postular una apertura del psicoanálisis.
138

Characterising the neural mechanisms of reward processing in bipolar disorder using EEG and fMRI

Mason, Liam January 2012 (has links)
One of the key features of bipolar disorder (BD) is risky and impulsive decision-making, behaviours theorised to arise from dysregulation in a biobehavioural system governing approach of rewards. However the neural mechanisms of this conceptual model have not been well specified, and there remains a gap between this model and key clinical phenomena such as mixed episodes. This thesis takes a neuroeconomics and reinforcement learning approach to characterise the neural mechanisms of motivational decision-making in BD. A review of the neurobiological evidence for reward dysregulation in BD (Chapter 1) arrives at a model in which striatal hypersensitivity is exacerbated by reduced dorsolateral prefrontal cortical (dlPFC) control. This model is tested by four studies using electrophysiology, source analysis and functional neuroimaging. Chapters 3 and 4 employ EEG to explore how hypomanic traits modulate motivational processing in contexts requiring learning and trade-offs between risk and between immediate and delayed reward. In Chapter 3, high trait hypomania was associated with impaired loss learning and a neural evaluation of rewards and losses more favourably, relative to low hypomania. This “rose-tinted” bias may reinforce risky behaviours that pay off and reduce learning from aversive repercussions. Chapter 4 reports an attentional bias towards immediate reward which may drive a steeper delay discounting trajectory and an inability to delay gratification. In Chapters 5 and 6 simultaneous electrophysiological and functional neuroimaging was utilised to characterise spatial and temporal perturbations to the mesocorticolimbic reward network in a clinical sample of BD. Patients showed a poorer ventromedial prefrontal cortical representation of the objective value of outcomes as well as a heightened striatal reward response. The latter finding was related to decreased dlPFC activation, which also interacted with residual manic symptoms. This is interpreted in terms of reduced top-down executive control that is exacerbated by residual manic symptoms, suggesting a potential mechanism underlying relapse and extremely high levels of reward-seeking seen during mania. EEG source imaging localised differences during reward outcome evaluation to early sensory-attentional (N1), reward evaluation (FRN) and cognitive (P300) stages of processing. For rewards, patients exhibited greater activity in precuneus, frontal eye fields (N1) and ventral anterior cingulate (FRN), consistent with an attentional bias to reward that drives hyperactivity in reward circuitry. Collectively the results provide evidence of reward dysfunction from behavioural measures and two neuroimaging modalities. The results support a model in which a core hypersensitivity to reward and a “rose-tinted” evaluation bias act to 1) potentiate the impact of rewarding outcomes and 2) attenuate aversive ones maintains a distorted representation of objective likelihood and value associated with actions. This is exacerbated by reduced prefrontal control – which may be particularly associated with mania – highlighting a potential target for novel pharmacological and psychological interventions.
139

Individual Perceptions of a Proposed Pressure to be Positive in America

Mitchell, Jessica L. 05 1900 (has links)
Positive psychology has become influential in research and practice. However, some have criticized positive psychologists who focus solely on the virtues of being positive. A tyrannical pressure to be positive may potentially exist in positive psychology, as well as mainstream United States culture. The following study explored perceptions of this theory using focus groups of individuals who differed in coping style, social desirability, and depression. Results suggest that individuals are affected by social pressures to be positive, and the expression of both positive and negative emotions is determined by social pressures, rules, context, and consequences. Although emotional expression, especially negativity, is contraindicated in several social contexts, there are also social, psychological, and physical benefits to all types of emotional expression.
140

The Reward Positivity and Depression: Investigating Possible Moderators

Roslyn B Harold (11662231) 22 November 2021 (has links)
The Reward Positivity (RewP) is a neurophysiological marker of reward sensitivity that has been found to be impacted in depression. However, there have been some mixed findings regarding the relationship between the RewP and depression, suggesting there are other factors which impact this relationship. The current study investigated how the demographic factors of sex, age, and socio-economic status might moderate the RewP-depression relationship, and examined if these effects generalize across three different inventories for symptoms of depression. 194 people were recruited by random digit dialing (55.2% male, mean age = 51.34 years, mean monthly income = $6625.95). They completed the SCID, HAM-D, and IDAS measures of depression, and an EEG session in which they did a random guessing task to elicit the RewP. We found that there was a trend-level interaction of a moderate effect size between symptoms of depression, age, and sex in predicting RewP amplitude. Further exploration of this interaction revealed that for females, there was an interactive effect between age and symptoms of depression, such that for younger females, increased symptoms of depression were associated with a blunted RewP, and lower symptoms of depression were associated with an enhanced RewP. These effects were specific to the SCID, but did not generalize to the HAM-D or IDAS. Moreover, there was no interactive effects between age and depression symptoms for males, nor did SES interact with depression and other demographic factors in predicting the RewP. This study provides evidence that demographic factors can impact the strength and nature of the relationships between the RewP and depression, and that future researchers might wish to over-sample younger females when investigating other moderating factors of the RewP in order to increase power.

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