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Dviprasmių figūrų suvokimo skirtingos suvokimo apkrovos užduotyse tyrimas sukeltųjų potencialų metodu / Research on the perception of ambiguous figures in different perceptual load tasks using the event-related potentials techniqueAntonova, Ingrida 23 December 2014 (has links)
Tokie regimieji dirgikliai kaip Necker’io gardelė įdomūs tuo, kad yra dviprasmiai bei sukelia trimatės erdvės pokyčio suvokimą. Remiantis suvokimo apkrovos teorija papildoma užduotis turėtų keisti šį suvokimą. Šio darbo tikslas buvo ištirti dviprasmių ir nedviprasmių gardelių suvokimą skirtingos suvokimo apkrovos užduotyse. I eksperimente dalyvavo 18 studentų (9 vyrai ir 9 moterys). Buvo tiriama didelės ir mažos suvokimo apkrovos įtaka reversijų suvokimui. II eksperimente dalyvavo 9 tiriamieji (7 vyrai ir 2 moterys). Tyrimo eiga buvo tokia pati kaip I eksperimento, bet skyrėsi užduotys: vienoje užduotyje raidžių nebuvo (normalus stebėjimas), kitoje užduotyje raidės buvo, bet į jas nereikėjo kreipti dėmesio. Palyginus abiejų tyrimų rezultatus nustatyta, kad bet kokia suvokimo apkrova panaikina Reversijos neigiamumą subjektyvaus pasikeitimo atveju. Realaus pasikeitimo bloke Reversijos neigiamumas buvo gautas, bet nepriklausė nuo apkrovos. Reversijos teigiamumui neturi įtakos nei suvokimo apkrova, nei suvokimo trukdis, tuo tarpu esant suvokimo trukdžiui Reversijos neigiamumas išnyksta tiek realaus, tiek Necker’io gardelės pasikeitimo atvejais. / Ambiguous visual stimuli such as the Necker lattice are interesting because they can cause apparent changes in our perception. According to the perceptual load theory, complementary tasks would be able to modify the amount of attention paid to this perception. The aim of this study was to investigate the perception of ambiguous and unambiguous lattices under different perceptual load tasks. Eighteen participants (9 men) took part in experiment I. The impact of high and low perceptual loads on perception of reversals was studied. 9 subjects (7 men) participated in experiment II. The experimental procedure was the same as in experiment I, but the tasks were a bit different: task without letters (normal observation) and task with letters distracters. Participants were told not to pay attention to letters in experiment II. A comparison of the results of these two experiments revealed that high and low perceptual loads eliminate Reversal Negativity in Necker change condition. Reversal Negativity was found in Real change condition, but it was load-independent. Neither perceptual load, nor load-resembling distractor have any effects on Reversal Positivity, however, Reversal Negativity was suppressed by load-resembling distractors both in Real change and in Necker change conditions.
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The power of negativity and its functioning in the metafictional text through five works : vladimir Nabokov’s Pale Fire, John Barth’s Coming Soon!!!, Graham Swift’s Waterland, Robert Coover’s Gerald’s Party and Don DeLillo’s White Noise. / Le pouvoir de la négativité et son fonctionnement dans le texte métafictionnel à travers cinq œuvres : pale Fire par Vladimir Nabokov, Coming Soon!!! par John Barth, Waterland par Graham Swift, Gerald’s Party par Robert Coover et White Noise par Don Delillo.Bouraoui, Jihene 27 October 2012 (has links)
La thèse se donne comme objectif l’appréhension des catégories de la négativité dans le texte métafictionnel en tant qu’une force libératrice et transformatrice qui, à la fois, assure la survie du texte malgré son aspect fragmentaire et multidirectionnel, et pousse le lecteur à s’engager dans une quête de l’insensé et du paradoxal qui n’embarque pas sur le nihilisme ‘négatif’, mais aboutit plutôt à la découverte de la face cachée constructive de la négativité, qu’est l’autocréation. Pour mener un tel projet, un assemblage littéraire de cinq œuvres disparates- Pale Fire par Vladimir Nabokov, Coming Soon!!! par John Barth, Waterland par Graham Swift , Gerald’s Party par Robert Coover et White Noise par Don Delillo- sert de terrain propice au travail de la négativité qui consiste essentiellement à démystifier et détruire des systèmes clos d’origine métaphysique et construire de nouveaux systèmes de valeurs, sans aucune prétention ou aspiration à la transcendance et la suprématie. Pour comprendre l’économie d’un tel texte, on va suivre trois étapes dont chacune correspond à une partie de la thèse : « L’éthique du texte métafictionnel », « L’esthétique du texte métafictionnel » et « La politique du texte métafictionnel ». La première partie s’engage à dégager l’ensemble d’impératifs éthiques qui mettent en œuvre la force de négativité. La deuxième partie s’engage à étudier les techniques de narration et d’écriture mises en œuvre pour activer les impératifs éthiques. La troisième partie s’engage à explorer la faisabilité et les limites des principes que l’on peut se construire en s’appropriant la négativité du texte. Le processus mis en œuvre dans les trois parties de la thèse est marqué par un combat perpetuel qui démontre l’aspect fallacieux et artificiel des construits et prouve, paradoxalement, notre incapacité de s’en passer pour exister. / The dissertation addresses the challenge to think the power of negativity and its ultimate constructive objective. It launches an enterprise, both at the textual and extratexual levels, that requires the individual to destroy and create at once, without any pretention to establish an everlasting system that dictates the encoding and decoding of thoughts and perception and management of cognitive, bodily and everyday life needs. Such an enterprise is based on the consideration of a literary assemblage of five novels: Vladimir Nabokov’s Pale Fire, John Barth’s Coming Soon!!!, Graham Swift’s Waterland, Robert Coover’s Gerald’s Party and Don Delillo’s White Noise. It demonstrates that the text is governed by an economy that does not embark on « negative » nihilism; it is rather an economy that transforms the unproductive forms (abyss, loss, spectre, madness, excess, death) into a capacity for resistance and a creative departure. It is an economy that sustains the text and prevents it from collapsing, through a set of ethical imperatives, a poetics of self-creation and a politics whose objective is not to resolve the paradoxes underlying the text. Throughout the three part of the dissertation, there is a continuous struggle to unveil the constructs and to explain the rationale behind our unavoidable need for them to keep going.
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Le temps du désir : ontologies de l'imaginaire et de l'affectivité chez Sartre, Merleau- Ponty et Grimaldi / The temporality of desire : ontologies of the imaginary and affectivity in the philosophies of Sartre, Merleau-Ponty and GrimaldiLapierre, Christopher 06 December 2013 (has links)
Le présent travail vise à confronter les ontologies de l’imaginaire de Sartre, Merleau-Ponty et Grimaldi. Empruntant la voie d’une critique du bergsonisme, chacune de ces philosophies s’élabore en accordant une valeur ontologique au négatif et en reconsidérant la signification de la temporalité. La réflexion sur le statut de l’image, et plus avant, sur les relations entre réel et imaginaire, présent et passé, conscient et inconscient, laisse émerger un sens original de la négativité. Merleau-Ponty et Grimaldi opposent ainsi à la dialectique de l’être et du néant l’idée d’une négativité qui pénètre l’être de part en part, le premier ouvrant la voie d’une alternative phénoménologique, le second lui préférant une alternative métaphysique. Ils prétendent par là, mieux que Sartre, rendre raison de la passivité de la subjectivité, de ses attaches dans l’être, source vive du mensonge à soi-même. Les limites de l’ontologie sartrienne trouvent leur origine dans une certaine idée de la conscience qui verrouille d’emblée les relations entre imagination et affectivité. C’est au contraire le libre jeu de cet axe qui rend possible le débordement de l’horizon de visibilité de la subjectivité en direction d’un certain invisible. La jonction concrète de l’imagination et de l’affectivité se déploie alors aux parages de la notion de désir, qui donne son sens rigoureux à la négativité dépistée initialement : à la différence de Sartre, Merleau-Ponty et Grimaldi pensent le caractère médiatisant de l’être compris comme désir et théorisent un décentrement radical de la subjectivité qui culmine pour l’un dans une pensée de l’intercorporéité, pour l’autre dans une éthique du don de soi. / This study aims at confronting the ontologies of the imaginary of Sartre, Merleau-Ponty and Grimaldi. Following the path of a critical assessment of Bergsonism, each of these philosophies develops by granting ontological value to the negative, and through a reconsideration of the meaning of temporality. A new approach of negativity emerges from the reflection on the status of the image and further, upon the relationships between real and imaginary, past and present, conscious and subconscious. Merleau-Ponty and Grimaldi thus reject dialectics of being and nothingness in favour of the idea of a negativity thoroughly penetrating being itself; the first one opening the way for a phenomenological alternative, and the second favouring a metaphysical alternative. They thereby claim to account, better than Sartre does, for the passivity of subjectivity, its rootedness in being–the living source of self-deceiving.The limitations of Sartrean ontology on the subject derive from a specific view of consciousness which locks off the relation between imagination and affectivity. On the contrary, the free play of this axis allows for the overflowing of the horizon of visibility of subjectivity toward a certain invisible. The concrete junction of imagination and affectivity then spreads out into the region of the notion of desire, which gives its determinate meaning to the negativity detected in the beginning. Unlike Sartre, Merleau-Ponty and Grimaldi study the mediatizing character of being understood as desire, and they theorize about a decentring of subjectivity culminating for Merleau-Ponty in a thought of intercorporeity and for Grimaldi in an ethics of self-sacrifice.
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A Geografia literária de Lêdo Ivo: a cidade nos romances As alianças e Ninho de cobras. / The literary geography in Ledo Ivo : the cuty in the novels As alianças and Ninho de cobras .Silva, Marcio Ferreira da 03 December 2007 (has links)
This study analyses the city representation in the novels As alianças and Ninho de
cobras from Lêdo Ivo. It introduces that the relations from several cultural stratus are
seen in the composition of the novels. This narratives show that there is also focus
on the city image, its meanings and unfolding in the contemporary world. This work
uses the bibliographical study and an analyses of qualitative nature, taking influence
in the cultural base studies done by Candido (1972; 2000), Bosi (2002); Hall (1997a;
1997b), Rama (1985) and Gomes (1994; 2004a; 2004b) and representation studies
done by Lima (2003) and Danto (2005). The analysis shows that both novels agree,
in literary form, what these authors discuss in their book. Concerning the city and its
discontinuous aspect, descriptive elements were detected in the novels in which
choices for negative categories are unchained, changing narrator, characters and
spaces into negative tone representations. Such negativity, as a novel
representation, instars in the post-naturalism, according to Bosi (2002), a pregnant
negativity that it s generated by an empty consciousness from the author. / Este trabalho analisa a representação da cidade nos romances As alianças e Ninho
de cobras, de Lêdo Ivo, discutindo como as relações de muitos estratos culturais se
apresentam na composição dos romances e permitem que se estabeleça, também,
um enfoque para a imagem da cidade, seus significados e desdobramentos no
mundo contemporâneo. Utiliza, para tanto, a pesquisa bibliográfica e uma análise de
natureza qualitativa, baseando-se, principalmente, nos estudos de base cultural
realizados por Candido (1972; 2000), Bosi (2002); Hall (1997a; 1997b), Rama (1985)
e Gomes (1994; 2004a; 2004b) e por estudos sobre representação feitos por Lima
(2003) e Danto (2005). A análise mostra que os romances configuram, na forma
literária, o que esses autores discutem. No que diz respeito à cidade e seu aspecto
descontínuo, detectaram-se elementos descritivos nos romances que desencadeiam
escolhas por categorias negativas, transformando narrador, personagens e espaços
em representações com tom elegíaco. A negatividade, como forma romanesca,
instaura no pós-naturalismo, segundo Bosi (2002), uma negatividade grávida ,
gerada por um vazio consciente da autoria.
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"Mé tělo dalo tvar jeho slávě". Dialogická poezie Louise Glückové / "His glory shined through my body." Dialogical poetry of Louise GlückBoháčová, Kristýna January 2018 (has links)
The thesis explores the variety of dialogue in the work of American poetess Louise Glück (*1943). It also points out three options for crossing over the aesthetics of absence. The analysis concerns mainly poems included in the collection The Wild Iris (1992), but it also takes in consideration Gluck's other poetical books such as Averno (2006) and Meadowlands (1996). After naming the nodes which make the contact in the collections, the thesis surpasses the field of literature for creating the dialogue with the aesthetics of absence according to German composer Heiner Goebbels (*1952), with the negative theology of French philosopher Simone Weil (1909-1943) and with the absence of the other in the paintings of Vilhelm Hammershøi (1864-1916). This interdisciplinary dialog seeks to describes one of the major tendencies of Gluck's poetry, which is the ghostly possibility of encountering with otherness
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A tradição do pensamento da negatividade (da negatividade à Kehre heideggeriana)Marçal Filho, José Carlos Gomes 05 December 2011 (has links)
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Previous issue date: 2011-12-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The aim of this work is thematically analyze the concepts of nothing, ontological difference and Dasein transcendence - and its structural developments into the concepts of, and Being destination - as concepts that can converge to a specific current of Western thought that we will cal as negativity thought tradition. This approach frees these concepts from the strict heideggerian´s thought body and allows us to glimpse a tradition that, despite the traditional metaphysical ontology, points to a more radical ontological dimension. This tradition is understood as initiated by Philo of Alexandria, followed by Ammonius Saccas and Jamblico, developed by Plotinus and Proclus and christianized by the mysticism of Dinonisius, the Areopagite and Master Eckhart. From this last on, we can establish a link between this tradition and the Heidegger´s thought.
We are not defining a mystical element into the Black Forest philosopher's thought, but providing clues that can harness the existential analytic approach and later developments of Heidegger's thought, the Kehre, with the the thinkers doctrines mentioned above. The links that will be established have convergences which can opening new possibilities up for thinking the collection of ancient ontology destruction, however, demonstrate that these similarities allow to contemplate the deeper dimension and these particular concepts and provide valuable clues for the interpretation not only within the Heidegger's thought, but also within the quoted tradition. It is a phenomenological-hermeneutic task capable of achieving a sense of historical and philosophical concepts, and finally set the parameters to define these points within the philosophy of Heidegger more clearly due to its link with a specific tradition. / O objetivo deste presente trabalho é analisar tematicamente os conceitos de nada, diferença ontológica e transcendência do Dasein e seus desdobramentos estruturais com os conceitos de , e destinamento do ser como conceitos que podem convergir para uma corrente específica do pensamento Ocidental que denominaremos de tradição do pensamento da negatividade. Tal abordagem liberta estes conceitos do corpo estrito do pensamento heidegerriano e nos permite vislumbrar uma tradição que, a despeito da ontologia metafísica tradicional, aponta para uma dimensão ontológica mais radical. Esta tradição é entendida como iniciada por Filon de Alexandria, seguida por Ammonius Saccas e Jâmblico, desenvolvida por Plotino e Proclo e cristianizada pelo misticismo de Dionisius, o Areopagita e Mestre Eckhart. Partindo deste último, poderemos estabelecer um vínculo entre esta corrente e o pensamento heideggeriano.
Não se trata aqui de delimitar um elemento místico no pensamento do filósofo da Floresta Negra, mas sim de fornecer pistas capazes de atrelar a abordagem da analítica existencial e os desdobramentos posteriores do pensamento de Heidegger, a Kehre, com as doutrinas dos pensadores acima citados. Os vínculos que serão estabelecidos possuem convergências que abrem novas possibilidades para pensarmos a destruição do acervo da antiga ontologia; entretanto, demonstraremos que tais similitudes permitem contemplar a dimensão mais profunda e particular destes conceitos e fornecer chaves valiosas de interpretação para os mesmos não apenas dentro do pensamento heideggeriano, mas também dentro da própria tradição que os funda. Trata-se de uma tarefa fenomenológica-hermenêutica capaz de conquistar o sentido histórico-filosófico destes conceitos e, finalmente, estabelecer os parâmetros para delimitarmos tais pontos dentro da filosofia de Heidegger com mais clareza devido ao seu nexo com uma tradição específica.
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Negatividade e participação: a influência do Pseudo Dionísio Areopagita em Tomás de Aquino - teologia, filosofia e educação / Negativity and participation: The influence of Pseudo-Dionysius Areopagite on Thomas Aquinas: Theology, Philosophy and Education.Roberto Carlos Gomes de Castro 13 November 2009 (has links)
Este trabalho sustenta que o teólogo cristão do início do século VI conhecido como Pseudo Dionísio Areopagita exerce profunda influência no pensamento do teólogo e filósofo medieval Tomás de Aquino (1225-1274). Essa influência se dá principalmente em dois temas fundamentais da filosofia tomasiana: negatividade e participação. Negatividade diz respeito ao caráter de mistério que envolve as essências mais íntimas dos seres desde a natureza visível e o homem até o princípio de todas as coisas, Deus e que, portanto, não são plenamente compreensíveis para o entendimento humano. Participação se refere ao fato de que, por outro lado, o mundo participa do ser de Deus e, por isso, revela traços do divino, ainda que de modo deficiente e remoto. Dada essa influência de Dionísio, Tomás de Aquino não pode ser considerado um pensador racionalista, com respostas definitivas para todos os problemas da existência, como costuma ser visto por epígonos o que constitui uma deturpação do pensamento tomasiano, marcado pela consciência da insuficiência da razão. Para Tomás, não é possível aos homens ter clareza absoluta sobre qualquer assunto, daí, por exemplo, a necessidade de eles se conduzirem segundo a clássica doutrina cristã da prudência a virtude de agir corretamente, com base no límpido conhecimento da situação presente. Tendo em vista a negatividade e a participação, para o acesso às realidades mais profundas impõe-se o uso de metáforas, alegorias e símbolos, capazes de algum modo de se aproximar do que, afinal, é incognoscível. No que se refere ao conhecimento de Deus, a via de acesso é a mística entendida como uma experiência com o Absoluto que se dá num plano além da razão, e não aquém , uma vez que todo discurso racional, afinal, fala mais do homem do que de Deus. Como conclusão, este trabalho propõe que o pensamento negativo do Pseudo Dionísio Areopagita e de Tomás de Aquino precisa ser mais conhecido também por educadores, pois ele permite uma visão diferente da realidade, uma visão menos lógico-racionalista que tantos problemas tem trazido à sociedade contemporânea e mais sensível, lúdica e profunda, portanto, mais humana. No anexo, é apresentada a tradução, direta do original grego, do livro Da teologia mística, do Pseudo Dionísio Areopagita. / This dissertation argues that the Christian theologian of the early sixth century known as Pseudo-Dionysius Areopagite exerts profound influence on the thought of medieval theologian and philosopher Thomas Aquinas (1225-1274). This influence is mainly on two major topics of Aquinas philosophy: negativity and participation. Negativity means the character of mystery that involves the most intimate essence of beings from the natural world and man to the cause of all things, God and therefore not fully comprehensible to human understanding. Participation refers to the fact that, on the other hand, the world participates in the being of God and, therefore, shows traces of the divine, even in a poor and remote way. Given the influence of Dionysius, Aquinas can not be regarded as a rationalist thinker, with definitive answers to all problems of existence, as is often seen by followers which is a perversion of Aquinass thought, marked by awareness of the insufficiency of reason. For Aquinas, it is not possible for men to have absolute clarity on any issue, then, for example, requiring them to conduct themselves according to the classical Christian doctrine of prudence the virtue of doing right, based on clear understanding of the current situation. Given the negativity and participation, accessing deeper realities requires the use of metaphors, allegories and symbols, which are able somehow to get closer to that, after all, is unknowable. With regard to knowledge of God, the way of access is the mystique understood as an experience of the Absolute that is given beyond reason, and not short , since all rational discourse, after all, speaks more about man than about God. In conclusion, this study suggests that the negative thought of Pseudo-Dionysius Areopagite and Thomas Aquinas should be more well known by educators, because it allows a different view of reality, less logical-rationalist that has brought many problems to contemporary society and more sensitive, playful and profound, therefore, more human. The annex includes a translation directly from the original Greek of The mystical theology, by Pseudo-Dionysius Areopagite.
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An electrophysiological investigation of reward prediction errors in the human brainSambrook, Thomas January 2015 (has links)
Reward prediction errors are quantitative signed terms that express the difference between the value of an obtained outcome and the expected value that was placed on it prior to its receipt. Positive reward prediction errors constitute reward, negative reward prediction errors constitute punishment. Reward prediction errors have been shown to be powerful drivers of reinforcement learning in formal models and there is thus a strong reason to believe they are used in the brain. Isolating such neural signals stands to help elucidate how reinforcement learning is implemented in the brain, and may ultimately shed light on individual differences, psychopathologies of reward such as addiction and depression, and the apparently non-normative behaviour under risk described by behavioural economics. In the present thesis, I used the event related potential technique to isolate and study electrophysiological components whose behaviour resembled reward prediction errors. I demonstrated that a candidate component, “feedback related negativity”, occurring 250 to 350 ms after receipt of reward or punishment, showed such behaviour. A meta-analysis of the existing literature on this component, using a novel technique of “great grand averaging”, supported this view. The component showed marked asymmetries however, being more responsive to reward than punishment and more responsive to appetitive rather than aversive outcomes. I also used novel data-driven techniques to examine activity outside the temporal interval associated with the feedback related negativity. This revealed a later component responding solely to punishments incurred in a Pavlovian learning task. It also revealed numerous salience-encoding components which were sensitive to a prediction error’s size but not its sign.
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Pouvoir et impouvoir du verbe : le dit, l'inter-dit, le silence : approche des oeuvres de Maurice Blanchot et Georges Bataille / The power and powerlessness of the verb : saying and silence in the works of Maurice Blanchot and Georges BatailleRadouk, Fatima 05 February 2010 (has links)
Qu'en est-il de la communication de l'impossible dans son rapport au pouvoir du langage ? En révélant la face a-dialectique du langage littéraire, Maurice Blanchot et Georges Bataille, liés par une amitié essentielle, ont redéployé l’espace désoeuvré de l’Impossible comme espace scripturaire. La présente étude s’est articulée en trois parties, regroupant chacune quatre chapitres. La première s’est intéressée à la nomination comme stricte révélation de la négativité, d’une part, et de l’altérité, d’autre part. Elle a analysé les stratégies de contestation du discours dialectique adoptées en vue de redessiner un nouvel espace communautaire grevé d’absence. Cette dernière, induisant par ailleurs le mouvement infini de la répétition, ouvre l’exigence scripturaire à l’in-fini du re-dire. La seconde a mis au centre de ses préoccupations, à l’exemple des auteurs eux-mêmes, la mort. Liée au déploiement scripturaire, la mort creuse littéralement le Dire dans lequel domine l’oscillation entre pouvoir et impouvoir. La dimension thanatique des œuvres des deux auteurs convoque les notions de limite, de transgression, de dehors, de chance et de neutre qui envisagent toutes l’ouverture de l’expérience scripturaire sur son impossible horizon. La dernière partie, quant à elle, a mis en évidence la manière dont l’écriture, en son mouvement disjoint et imaginaire, s’abstrait du domaine du possible en s’ouvrant finalement sur le silence dont elle se fait complice pour ouvrir le Dire au partage de l’Impossible. / This thesis discusses the saying of the Impossible in its relationship to the power of language in the works of Maurice Blanchot and Georges Bataille. By unveiling the a-dialectical aspect of the literary language, Maurice Blanchot and Georges Bataille, who were bound by an essential friendship, deployed anew the idle space of the Impossible as a writerly space. This study is composed of three parts, each divided into four chapters. The first part discusses nomination as a strict unveiling of negativity on the one hand, and of alterity on the other hand, before analysing the strategies of contesting the dialectical discourse which were adopted by both writers with a view of delineating a new community space marked by absence. By inducing an endless movement of repetition, absence is shown to open the writerly exigence to the infiniteness of re-saying. The second part focuses on death as explored by both writers themselves. As linked to the writerly deployment, death literally enacts a saying dominated by the oscillation between Power and Unpower. The thanatical dimension of the works of both authors relies on the notions of limits, transgression, exteriority, chance and neutre, all of which lead to the opening of the writerly experience on its impossible horizon. The third part highlights how writing, in its disjointed and imaginary movement, abstracts itself from the realm of the possible by opening itself to the silence and becoming thus its accomplice to open the saying to the sharing of the Impossible.
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Le rôle du cortex frontal médian dans la supervision de l'action chez l'homme : études électrophysiologiques / The role of medial frontal cortex in action monitoring in humans : electrophysiological studies of outcome modulated activitiesBonini, Francesca 21 July 2016 (has links)
La capacité à évaluer les résultats nos actions est fondamentale pour adapter et optimiser notre comportement et dépend d’un système superviseur chargé d’évaluer l’action, détecter les erreurs, déclencher des corrections.Le réseau neuronal sous-jacent la supervision de l’action n’a pas été complètement caractérisé chez l’homme.Dans une première étude nous avons enregistré dans l’Aire Motrice Supplémentaire (AMS) des LFP évoqués par les réponses et modulés par la performance. Des LFP évoqués exclusivement par les erreurs ont été enregistrés plus tardivement dans le cortex préfrontal médian.Dans la deuxième étude, nous avons observé que les activités de hautes-fréquences gamma sont, elles aussi, modulées par la performance des sujets, mais dans un vaste réseau frontal et extra-frontal.Dans une troisième étude, utilisant des enregistrements simultanés électroencéphalographiques (EEG) et magnétoencéphalographiques (MEG), nous observé une activité évoquée par un feedback interne sur l’EEG (mais pas en MEG), alors qu'une activité évoquée par le feedback externe était bien visible sur les enregistrements MEG, indiquant que les générateurs de ces deux activités cérébrales, sont différents. Nos résultats montrent une implication de l’AMSp dans la supervision de l’action chez l’homme, bien plus importante que ce que l’on soupçonnait auparavant. L’AMS évalue précocement, et de façon continue, l’action en cours et elle engage vraisemblablement des structures préfrontales en cas d’erreur seulement. Le traitement de l’erreur d’action, selon qu'il se fonde sur des informations internes ou externes est certainement sous-tendu par des réseaux corticaux différents. / The capacity to evaluate the outcome of our actions is fundamental for adapting and optimizing behaviour. This capability depends on an action monitoring system in charge of assessing ongoing actions, detecting errors, and evaluating outcomes.Electrical brain activity evoked by negative outcomes is thought to originate within the medial part of the frontal cortex. Nonetheless, the underlying neuronal network is incompletely characterised in humans.In the two first studies, we investigated the anatomical substrates of action monitoring in humans using intracerebral local field potential (LFP) recordings of cerebral cortex from epileptic patients. Response evoked LFPs sensitive to outcome were recorded from the Supplementary Motor Area proper (SMA), while LFPs evoked exclusively by errors were recorded later in the medial prefrontal cortex. High-gamma-frequency activity (60-180 Hz) was modulated as a function of action outcome in a vast frontal and extra-frontal network.In a third study using simultaneous recording of electroencephalography (EEG) and magnetoencephalography (MEG), we found that error related activity was detected by EEG (but not by MEG), while feedback-related activity was detected by MEG, indicating that the sources of these two forms of outcome-modulated brain activity are different.To conclude the SMA is much more involved in action monitoring than previously thought. SMA rapidly and continuously assesses ongoing actions and likely engages more rostral prefrontal structures in the case of error. Processing of action errors and of negative externally delivered feedback therefore appears to be supported by distinct cortical networks.
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