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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.
81

O debate da imagética mental / The imagery debate

Patricia Fernandes Battilani 21 March 2013 (has links)
O debate da imagética mental consiste de uma controvérsia iniciada nos anos 1970 a respeito da forma das representações mentais, e foi travada principalmente entre Stephen Kosslyn, que propunha uma forma imagética, e Zenon Pylyshyn, que propunha um formato simbólico-estrutural, além de apontar falhas conceituais na teoria da afiguração implícita no modelo pictorialista. Nesta dissertação, apresenta-se um balanço filosófico deste debate, levando em conta também críticas adicionais de Daniel Dennett aos pressupostos da abordagem pictorialista. / The mental imagery debate is a controversy that began in the 1970s concerning the form of mental representation, and was carried out mainly by Stephen Kosslyn, who defended a picture-like representation, and Zenon Pylyshyn, who proposed a symbolic-structural format. The latter also pointed out conceptual problems of the pictorialist model. This thesis presents a philosophical discussion of the debate, also taking into account additional criticisms by Daniel Dennett to the presuppositions of the pictorialist approach.
82

Étude des mouvements oculaires au cours de l’imagerie mentale visuelle, chez les sujets sains et chez ceux atteints d’une négligence représentationnelle ou d’une hémianopsie latérale homonyme / Eye movements during visual mental imagery in healthy subjects and in patients with representational neglect or lateral homonymous hemianopia

Fourtassi, Maryam 14 December 2016 (has links)
L'imagerie mentale visuelle est généralement accompagnée de mouvements spontanés des yeux qui ne sont pas arbitraires mais reflètent le contenu spatial de cette imagerie. Ce travail de thèse avait pour principal objectif l'utilisation de l'enregistrement des mouvements oculaires afin d'étudier les représentations mentales chez les sujets sains et les sujets atteints de lésions cérébrales et ainsi d'en explorer les mécanismes, la dynamique, les référentiels et les substrats neuronaux. Nous avons enregistré les mouvements des yeux pendant le rappel des villes de France à partir de la mémoire à long terme, soit en ayant recours à l'imagerie mentale de la carte de France, soit avec un accès sémantique (tâche de fluence verbale). Ce paradigme a été réalisé dans 3 situations différentes : chez les sujets sains avec le regard libre, chez les sujets sains avec le regard fixé et chez les sujets atteints de négligence spatiale unilatérale et/ou hémianopsie latérale homonyme (HLH) avec le regard libre. En utilisant la corrélation bi-dimensionelle (BDR) entre les positions oculaires et les positions GPS des villes évoquées par le sujet, nous avons pu réaliser dans ces trois situations une analyse individuelle. Chez les sujets sains en regard libre, nous avons démontré que l'imagerie mentale se construit de façon séquentielle, et fragmentée, et que la corrélation significative est une signature individuelle de l'utilisation de l'imagerie visuelle. Chez les sujets sains avec le regard fixe, nous avons mis en évidence l'existence de microsaccades qui reflètent toujours le contenu spatial de l'imagerie mentale pour la plupart des individus. Chez les négligents, la représentation mentale de la carte de France était perturbée aussi bien dans le référentiel allocentrique (absence de cohérence spatiale pour les villes de la moitié gauche) que dans le référentiel égocentrique (carte mentale décalée du côté ipsilésionnel). Chez les patients avec HLH, la représentation mentale était décalée du côté contra-lésionnel, mais était spatialement cohérente dans le référentiel allocentrique. Cette nouvelle approche méthodologique et statistique a permis de discuter les différentes interprétations théoriques de la littérature concernant les liens entre mouvements des yeux et imagerie mentale, et d'étudier les troubles de représentation spatiale faisant suite à la lésion du cortex visuel primaire et du réseau pariéto-frontal droit, substrats respectifs du tampon visuel et de la fenêtre attentionnelle / analyse des relations spatiales dans le modèle d'imagerie de Kosslyn / Visual mental imagery is usually accompanied by spontaneous eye movements that are not random but reflect the spatial content of the imagery. The main objective of this thesis was to use eye movements recording in order to explore the mechanisms, the dynamics, the reference frames and the neural processes of spatial representations in healthy subjects and brain damaged patients.We recorded eye movements during the verbal recall of french cities from long-term memory, either through mental imagery of the map of France, or through a semantic access (verbal fluency task). This paradigm was carried out in three different situations: In healthy subjects with free gaze, in healthy subjects with fixed gaze and in patients with unilateral spatial neglect and / or homonymous hemianopia with free gaze. Using bi-dimensional regression (BDR) between ocular positions when cities were evoked and GPS positions of these cities, we could provide an individual analysis in each of these three situations.In healthy subjects with free gaze, we demonstrated that mental imagery is built sequentially and fragmented, and that significant correlation is a signature, at an individual level, of the use of visual imagery. In healthy subjects with central gaze fixation, we have demonstrated that the remaining microsaccades still reflect the spatial content of the imagery in most individuals. In patients with hemineglect, the mental representation of the map of France was disturbed both in the allocentric reference frame (lack of spatial coherence for cities of the left side) and in the egocentric reference frame (mental map shifted ipsilesionally). In subjects with hemianopia, the mental image was shifted contralesionally but was spatially coherent in the allocentric frame.These results are discussed in the light of the different theories on eye movements and mental imagery found in the literature and in particular with respect to the Kosslyn model of imagery in which the primary visual cortex (damaged in hemianopia) corresponds to the substratum of the visual buffer and the right parieto-frontal network to the substratum of the the attentional window and the spatial properties processing system
83

Métrologie sensorielle olfactive et apprentissage olfactif appliqués à l’œnologie / Metrology and olfactory learning applied to oenology

Tempère, Sophie 06 December 2010 (has links)
L’agrément d’un vin dépend du jugement de ses qualités organoleptiques par un jury de professionnels. Les performances olfactives et gustatives nécessaires des dégustateurs y jouent un rôle déterminant. Pourtant jusqu’ici, ces aptitudes sensorielles fondamentales n'étaient pas directement prises en compte par les professionnels. Même si l’on peut donner une définition de l'expert, en préciser les capacités nécessaires, de multiples études ont mis en relief l’hétérogénéité des appréciations individuelles de dégustation et le manque de consensus forts. La littérature illustre les différences d’expertises entre professionnels et novices, mais aucune étude ne s’intéresse à l’amplitude des différences sensorielles interindividuelles chez les experts.Nos recherches nous ont conduit à caractériser les capacités olfactives de la population des professionnels du vin et à mesurer leur influence sur l’appréciation d’un vin. Nos mesures ont montré la variété interindividuelle des capacités perceptives, des appréciations hédoniques et des capacités cognitives recrutées par le traitement de l’information olfactive chez les professionnels du vin. Nos expériences ont suggéré que ces différences interindividuelles, relatives notamment à la sensibilité et l’appréciation hédonique, influencent la perception et le jugement d’un même vin par les experts. Cependant les résultats confirment aussi la possible influence de la dimension cognitive liée au vécu du sujet sur la perception olfactive plus ou moins complexe et l’apprentissage olfactif. Finalement, ce travail permet de déterminer des besoins en formation. Nous proposons en conséquence des outils pratiques d’évaluation des capacités sensorielles et des pédagogies d’entraînement adaptées. C'est l'occasion de souligner la pertinence de certains facteurs cognitifs dans l’amélioration des performances olfactives, tels que ceux impliquant l’attention ou l'imagerie mentale olfactives. / The quality of a wine is measured primarily by experts who evaluate its organoleptic features. Their olfactory and gustatory capacities are decisive, but these experts do not appreciate their own sensory abilities. Moreover, although we can give a clear definition of the expertise, several studies have shown that professionals are often confronted with disparities in their wine assessment. Several studies have also shown the differences between experts and novices, but no attention was paid to the diversity of the chemosensory abilities of the experts.At the Oenology Faculty in Bordeaux, with voluntary participation of the professionals, we characterized the olfactory performances of wine professionals and measured their impact on the wine assessment.The results showed significant inter-individual variation in olfactory sensitivities, hedonic ratings and cognitive abilities among the wine professionals. Further, our experiments have suggested that these inter-individual differences, especially concerning the sensitivity and the hedonic appreciation, influence perceptions and judgments of a same wine by the experts. However, the results confirm the possible influence of the cognitive dimensions related to the experience of the subject on their perception and their olfactory training. Finally, this work identifies training needs. We therefore propose and test practical tools for assessment of sensory performances and appropriate sensorial training. This has been an opportunity to highlight the potential role of attention or olfactory mental imagery in the improvement of the olfactory performance.
84

Media form and ESL students’ comprehension : A comparative study between audiobooks and printed text

Andrén, Kim January 2020 (has links)
This study aims to investigate how the choice of media form, i.e. printed format, audiobook or reading and audio combined, affect the ability of ESL students to achieve comprehension, and how different ways of asking questions can affect their comprehension ability. Lastly, the study aims to investigate the relationship between comprehension and students’ proficiency levels in their L2. To answer this question, 155 students were recruited and divided into three groups and assigned one type of media form. The quantitative data was collected through an online comprehension test and analysed. The results showed a significant difference between the media forms and revealed that printed reading was superior. However, a printed and audio combination was the most time efficient way for students to achieve comprehension, which indicates that the inclusion of audio does not impede student learning. Previous research in the same field shows that the results are inconclusive, but shares one common conclusion, that students enjoy the audio format. As a result, the educational system should make every effort to media choices for students to choose their preferred media, and more research in the field needs to be done, as students enjoyment leads to increased learning.
85

[en] AUTOBIOGRAPHICAL MEMORIES AND MENTAL IMAGERY: AN EMOTIONAL REGULATION AND RECONSOLIDATION STUDY / [pt] MEMÓRIAS AUTOBIOGRÁFICAS E IMAGINAÇÃO: UM ESTUDO DE REGULAÇÃO EMOCIONAL E RECONSOLIDAÇÃO

17 March 2021 (has links)
[pt] A presente dissertação tem como objetivo explorar a conexão entre memórias autobiográficas (MA) e imagética mental (IM) através de uma revisão sistemática e um estudo empírico. A presente revisão investiga o papel da AM e MI como procedimentos de indução de humor (PIH). Os resultados em geral sugerem que uma variedade de pistas tem sido usada para evocar MA ou IM. Verificou-se também que poucos estudos relataram resultados estatísticos sobre a eficácia dos métodos, controle dos efeitos de demanda ou empregaram medidas fisiológicas da emoção. Recomenda-se um trabalho adicional para investigar as implicações dessas questões metodológicas. O estudo empírico explorou os efeitos das tarefas IM (positivo ou neutro) sobre a MA de adultos jovens saudáveis. Na Sessão 1, os participantes se lembraram de um evento triste. Dependendo do grupo, eles deveriam imaginar um cenário alternativo positivo ou neutro para a memória. Duas semanas mais tarde, na Sessão 2, eles tiveram que completar a mesma tarefa de memória. Os resultados indicam que os PIHs foram eficazes, com aumentos no humor negativo após a MA triste e melhorias no humor em ambos os grupos após IM, independentemente do seu conteúdo emocional. Isso sugere que as IMs podem ser usadas como uma estratégia eficaz de regulação emocional para o material autobiográfico negativo, e que o conteúdo emocional das imagens pode não ter um impacto crucial nesse processo, porém são necessários mais estudos para realizar esta avaliação, explorar diferentes tipos de memória emocional e estender esse paradigma para populações clínicas. / [en] The current dissertation aims to explore the connection between autobiographical memories (AM) and mental imagery (MI) through a systematic review and an empirical study. The present review investigates the role of AM and MI as mood induction procedures (MIP). Results broadly suggest that a variety of cues to elicit AM or MI has been used. It was also found that few studies reported statistical results about the methods efficacy, control for demand effects, or employed physiological measures of emotion. Further work investigating the implications of these methodological issues is recommended. The empirical study explored the effects of MI tasks (positive or neutral) on AM of healthy young adults. In Session 1, participants remembered a sad life event. Depending on their group, they should imagine either a positive or a neutral alternative scenario to the memory. Two weeks later, in Session 2, they had to complete the same memory task. Results indicate that MIPs were effective, with increases in negative mood after the sad AM and improvements in mood in both groups after imagery regardless of its emotional content. Memory report revealed that groups had a similar profile of memory intrusion. This suggests that mental imagery may be used as an effective emotional regulation strategy for negative autobiographical material, and that the emotional content of imagery may not have a crucial impact in this process. Further studies are needed to evaluate the use of imagery as emotional regulation, explore different types of emotional memory and extend this paradigm to clinical populations.
86

A Study on The Influence of Visual Electronic Word of Mouth (VeWOM) On Consumer Travel Intention: A Mental Imagery Processing Perspective from A Developing Markets Context

Zimba, Chitivwa January 2022 (has links)
The full text will be available at the end of the embargo: 15th Dec 2026
87

Changing Focus: From Second / Foreign Language Teaching to Communication Learning

Postica, Adina M. 20 June 2006 (has links)
No description available.
88

A clinical neuroscience investigation into flashbacks and involuntary autobiographical memories

Clark, Ian Alexander January 2013 (has links)
Recurrent and intrusive distressing recollections of trauma are a hallmark symptom of Posttraumatic Stress Disorder (PTSD). The term ‘flashback’ is used in this thesis to refer to vivid, sensory perceptual (predominantly visual images), emotional memories from a traumatic event that intrude involuntarily into consciousness. Furthermore, intrusive image based memories occur in a number of other psychological disorders, for example, bipolar disorder and depression. Clinically, the presence and occurrence of flashbacks and flashback type memories are well documented. However, in terms of the neural underpinnings there is limited understanding of how such flashback memories are formed or later involuntarily recalled. An experimental psychopathology approach is taken whereby flashbacks are viewed on a continuum with other involuntary autobiographical memories and are studied using analogue emotional events in the laboratory. An initial review develops a heuristic clinical neuroscience framework for understanding flashback memories. It is proposed that flashbacks consistent of five component parts – mental imagery, autobiographical memory, involuntary recall, attention hijacking and negative emotion. Combining knowledge of the component parts helped provide a guiding framework, at both a neural and behavioural level, into how flashback memories may be formed and how they return to mind unbidden. Four studies (1 neuroimaging, 3 behavioural) using emotional film paradigms were conducted. In the first study, the trauma film paradigm was combined with neuroimaging (n = 35) to investigate the neural basis of both the encoding and the involuntary recall of flashback memories. Results provided a first replication of a specific pattern of brain activation at the encoding of memories that later returned as flashbacks. This included elevation in the rostral anterior cingulate cortex, insula, thalamus, ventral occipital cortex and left inferior frontal gyrus (during just the encoding of scenes that returned as flashbacks) alongside suppressed activation in the left inferior frontal gyrus (during the encoding of scenes that returned as flashbacks in other participants, but not that individual). Critically, this is also the first study to show the brain activation at the moment of flashback involuntary recall in the scanner. Activation in the middle and superior frontal gyri and the left inferior frontal gyrus was found to be associated with flashback involuntary recall. In the second study, control conditions from 16 behavioural trauma film paradigm experiments were combined (n = 458) to investigate commonly studied factors that may be protective against flashback development. Results indicated that low emotional response to the traumatic film footage was associated with an absence of flashbacks over the following week. The third study used a positive film to consider the emotional valence of the emotion component of the framework. Positive emotional response at the time of viewing the footage was associated with positive involuntary memories over the following week. The fourth study aimed to replicate and extend this finding, comparing the impact of engaging in two cognitive tasks after film viewing (equated for general load). Predictions were not supported and methodological considerations are discussed. Results may have implications for understanding flashbacks and involuntary autobiographical memories occurring in everyday life and across psychological disorders. Further understanding of the proposed components of the clinical neuroscience framework may even help inform targeted treatments to prevent, or lessen, the formation and frequency of distressing involuntary memories.
89

Générativité : nouvelle conceptualisation et examen du rôle médiateur de l'imagerie mentale et de la générativité situationnelle dans le processus persuasif prosocial : application au don du sang placentaire / Generativity : new conceptualization and examination of the mediator role of mental imagery and situational generativity in the persuasive prosocial process : application to the umbilical blood cord donation

Assaf, Cynthia 06 December 2018 (has links)
De nombreux facteurs environnementaux et/ ou de santé publique amènent à se poser aujourd’hui la question du devenir des générations futures. Plusieurs fléaux touchent notre société et sont de nature à affecter les générations suivantes à l’instar de nombreuses maladies dégénératives, de cancers, de maladies génétiques et diverses maladies de sang et de la moelle osseuse. Cependant, un élément d’optimisme a vu le jour grâce à la possibilité de prélever le sang placentaire et de conserver les cellules souches du cordon ombilical du nouveau-né à des fins de greffes ultérieures, beaucoup moins lourdes que celles de moelle osseuse. Des actions de communication seraient donc utiles pour informer les parents de cette possibilité, les sensibiliser et les encourager à prendre la décision de conserver les cellules souches du cordon pour le bien des générations futures. Ce besoin de communication et la nécessité de se préoccuper des générations futures ont attiré notre attention sur un concept issu de la psychologie sociale et introduit récemment en marketing : la générativité, définie par son auteur pionnier comme étant « la préoccupation quant à l’établissement et au conseil des générations futures » (Erikson, 1950). Par conséquent, la problématique centrale de cette recherche s’articule comme suit : Comment construire des messages prosociaux incitatifs, favorables aux générations futures, - en l’occurrence de conservation des cellules souches du sang du cordon ombilical -, efficaces pour agir sur les attitudes et intentions des femmes enceintes par une stimulation de leur générativité situationnelle ? Les objectifs de cette recherche imposent avant tout de mener une phase primordiale de meilleure compréhension du concept de générativité et de sa mesure. À cet effet, deux études préliminaires (étude qualitative suivie d’une étude quantitative) ont permis de mieux cerner ce concept du point de vue de ses conceptualisation, opérationnalisation et mesure. Une nouvelle conceptualisation de la générativité fondée sur une générativité situationnelle, venant compléter l’unique vision dispositionnelle de préoccupation générative, est proposée. Ensuite, une expérimentation auprès de femmes enceintes, cible de la décision de don du sang placentaire, souligne le rôle de l’imagerie mentale et de la générativité situationnelle dans le processus persuasif, confirmant la pertinence de cette nouvelle conceptualisation. Enfin, les résultats sont discutés ; des voies de recherches sont développées, notamment pour pallier les limites de la présente recherche. / Many environmental and/ or public health factors lead to questioning the future of generations. Many plagues affect our society and are likely to influence future generations such as numerous degenerative or genetic diseases, cancers, blood and bone marrow disorders. However, an optimistic element has emerged due to the ability to collect placental blood and to preserve the umbilical cord stem cells of the newborn for subsequent grafts, less heavier than those of bone marrow. Communication actions would therefore be useful to inform parents of this possibility, raise awareness and encourage them to decide to conserve cord stem cells for the benefit of future generations. This need for communication as well as the concern toward future generations have drawn our attention to a concept that emerged from social psychology and has been recently introduced into marketing: generativity. Erikson (1950), its pioneer, defined it as « primarily the concern in establishing and guiding the next generation ». Our central research question is articulated as follows: How to construct incentive prosocial messages, favorable to future generations, - in our case the conservation of umbilical cord stem cells -, effective in influencing the attitudes and intentions of pregnant women by stimulating their situational generativity? The objectives of this research require, first and foremost, a crucial phase of better understanding the concept of generativity and its measurement. To this end, two preliminary studies (qualitative followed by a quantitative study) made possible to perceive the conceptualization, operationalization and measurement of this concept. A new conceptualization of generativity based on a situational vision, in addition to the dispositional vision of generative concern, is proposed. Afterwards, an experiment among pregnant women, potential decision makers in donating placental blood, highlights the role of mental imagery and situational generativity in the persuasive process, confirming the relevance of this new conceptualization. Finally, the results are discussed ; research perspectives are developed, particularly to overcome the limitations of this research.
90

Etude des réseaux neuronaux impliqués dans les troubles de la marche et le freezing dans la maladie de Parkinson / Study of the cerebral networks involved in gait disorders and freezing in Parkinson's disease

Maillet, Audrey 07 December 2012 (has links)
Les troubles de la marche et le freezing entraînent une invalidité sévère et ont un impact important sur la qualité de vie des patients souffrant de la maladie de Parkinson (MP). Ceci est d'autant plus vrai que ces troubles répondent mal aux traitements actuels, médicamenteux et chirurgicaux. Leurs mécanismes physiopathologiques sont largement incompris. Toutefois, leur résistance aux traitements courants suggère l'extension du processus lésionnel vers des structures non-dopaminergiques concourant au contrôle de la locomotion. L'implication du noyau pédonculopontin (PPN) a été évoquée. L'objectif de cette étude était de mieux comprendre les circuits neuronaux impliqués dans ces troubles, ainsi que leur modulation par les médicaments dopaminergiques et la stimulation du PPN. Les contraintes d'immobilité de la tête, liées à l'utilisation de la technique de tomographie par émission de positons (TEP), excluant la réalisation d'une épreuve effective de marche, la tâche a été effectuée en imagerie mentale. Les mêmes réseaux neuronaux sont en effet activés lors de la réalisation effective et la représentation mentale d'un mouvement, sous réserve que l'imagerie mentale motrice soit réalisée selon une perspective dite kinesthésique. Il était donc nécessaire, au préalable, de vérifier l'aptitude des patients à imager leur marche selon cette modalité. Nos données vont dans ce sens, et montrent qu'il est possible d'améliorer cette capacité à travers une préparation spécifique. De plus, l'utilisation d'un protocole comportemental d'imagerie mentale reposant sur la loi de Fitts a permis de familiariser les patients avec la tâche d'imagerie mentale en amont de la réalisation des examens TEP, mais aussi de vérifier leur engagement dans cette dernière durant les acquisitions cérébrales. Les résultats obtenus à l'issue de l'étude menée en imagerie cérébrale confirment la complexité de la physiopathologie des troubles locomoteurs, et suggèrent notamment différents niveaux d'atteinte, à l'étage cortical, sous cortical, et du tronc cérébral, selon la nature dopa-sensible ou dopa-résistante du trouble concerné. En particulier, la dérégulation frontale semble confirmée. De plus, un dysfonctionnement du tronc cérébral pourrait être lié à l'émergence des troubles de la marche et du freezing. Nous avons également constaté une implication pariétale, mais son rôle compensateur, ou pathologique, reste encore à définir. Le freezing dopa-sensible pourrait en partie refléter l'expression aggravée de la bradykinésie parkinsonienne, étant donné l'efficacité de la lévodopa sur ce symptôme. La stimulation de la région des PPN semble quant à elle restaurer une boucle cortico-cérebello-thalamo-corticale, facilitant le mouvement dans le cas des troubles dopa-résistants. Des investigations complémentaires, sur un échantillon plus large de patients, sont donc nécessaires pour approfondir ces résultats. Une meilleure compréhension de la physiopathologie de ces troubles est en effet indispensable pour le développement de nouvelles thérapeutiques dans le but d'améliorer la prise en charge des patients souffrant de ces troubles invalidants, et ainsi leurs répercussions en termes de santé publique. / Gait disorders, including freezing of gait are frequent and disabling symptoms that lead to severe decrease of the quality of life on patients from Parkinson's disease (PD). This is emphasized by the fact that those difficulties respond poorly to current medical and surgical treatments. The underlying pathophysiology remains largely unknown. However, the resistance to actual treatments suggests the extension of the degenerative process towards non-dopaminergic structures. Involvement of the pedonculopontine nucleus (PPN) has been proposed. The aim of the study was to better understand the neural networks involved in those troubles, as well as their modulation by dopaminergic drugs and PPN stimulation. The constraints related to stillness of the head during Positron Emission Tomography (PET) exclude, necessarily, the realization of an effective gait. This task has been accomplished using mental moor imagery. The same mural networks are, indeed, activated during the actual execution and the mental representation of movement, under the assumption that motor mental imaging is undertaken from a kinesthetic perspective. Thus, it was necessary, preliminarily to this study, to control the ability of patients to imagine themselves walking from a kinesthetic point of view. Our data validate this condition. Moreover, they show that it is possible to improve this ability through a specific training. What is more, the use of a behavioral protocol, based on Fitt's law, helped the patients to familiarize themselves with this approach, before PET acquisitions, but also to control their correct performance during PET scan. The results, which have been obtained in cerebral imaging confirm the complexity of the underlying mechanisms of gait disorders, and suggest notably different levels of deregulation, on a cortical, sub-cortical and brainstem. In particular, frontal deregulation appears to be confirmed. Moreover, a deregulation of the brainstem could be more particularly involved in gait disorders apparition. We have also evidenced parietal implication, but its exact compensatory or pathologic role remains to be determined. Levodopa-responsive freezing seems to be a consequence of worsened parkinsonian bradykinesia. PPN stimulation seems able to restore a functional cortico-cerebello-cortical loop, facilitating movement. Complementarily studies, on a larger selection of patients, are thus necessary to complete those results. A better understanding of pathophysiology is, as a matter of fact, necessary for the development of new therapeutics in order to improve the therapy of patients from those very invalidating troubles, and thus, to reduce their impact on public health.

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