Previous research and current models have proposed that the right temporoparietal junction (rTPJ) is crucially involved in the control and distinction of shared representations of action. Hitherto, this assumption has mainly been based on neuroimaging work ( (Spengler, von Cramon, & Brass, 2009); (Spengler, von Cramon, & Brass, 2010)) We tested this hypothesis, that the rTPJ is causally involved in managing shared representations by using repetitive transcranial magnetic stimulation in an offline paradigm to disrupt neural activity in this region. Using a simple imitation-inhibition task we showed that stimulation of the rTPJ led to increased reaction times when participants had to control automatic imitation of a perceived hand movement, as they had to concurrently plan and execute an opposite movement. Our study provides the first empirical evidence that the rTPJ is necessary for managing and navigating within a shared representational system. These results may also have important implications for future theorizing about the role of the TPJ region in controlling shared representations also in other domains, such as somatosensation or emotional experiences.:1 Bibliografische Beschreibung 2 Introduction 2.1 Imitation 2.1.1 Automatic imitation and mirroring 2.1.2 Control of automatic imitation 2.2 Functional Neuroanatomy 2.2.1 Temporo-parietal junction (TPJ) 2.2.2 Function of the right TPJ 2.3 Transcranial magnetic stimulation (TMS) 2.3.1 History 2.3.2 Physical Basis of TMS 2.3.3 TMS stimulatore 2.3.4 rTMS 2.3.5 Medical Use 3 Own Study: Aims and research questions 3.1 Research Questions 4 Materials and Methods 4.1 Participants 4.2 General procedure 4.3 Imitation-Inhibition task 4.4 TMS- protocol 4.5 Data analysis 5 Results 6 Discussion 7 Conclusion 8 Literatur directory 9 Figures and Table 10 Curriculum Vitae 12 Erklärung über die eigenständige Abfassung der Arbeit

The diploma thesis deals with the topic of neurocognitive changes in schizophrenia and the possibility of non-pharmacological interventions. It first summarizes current knowledge about schizophrenia, in connection with interdisciplinary overlaps enabling orientation in the topic. The thesis describes the individual cognitive disorders that are part of the disease. The main focus of the work is to inform about the possibilities of cognitive remediation. We focus on cognitive training and transcranial direct current stimulation in more detail. In particular, the use of stimulation methods has not yet been described in Czech literature. The work should thus contribute to the mapping of this issue. The theoretical part is followed by an empirical presentation of the results of our pilot study. In the study, we use a quantitative-qualitative methodology to map objective and subjective changes in cognitive functions before and after the application of stimulation and cognitive training in patients with schizophrenia. We included 9 patients who met the entry criteria. The results of the quantitative part did not reveal significant changes after the application of active tDCS stimulation in combination with cognitive training. The qualitative part of the study described subjectively perceived changes and...

The diploma thesis deals with the topic of neurocognitive changes in schizophrenia and the possibility of non-pharmacological interventions. It first summarizes current knowledge about schizophrenia, in connection with interdisciplinary overlaps enabling orientation in the topic. The thesis describes the individual cognitive disorders that are part of the disease. The main focus of the work is to inform about the possibilities of cognitive remediation. We focus on cognitive training and transcranial direct current stimulation in more detail. In particular, the use of stimulation methods has not yet been described in Czech literature. The work should thus contribute to the mapping of this issue. The theoretical part is followed by an empirical presentation of the results of our pilot study. In the study, we use a quantitative-qualitative methodology to map objective and subjective changes in cognitive functions before and after the application of stimulation and cognitive training in patients with schizophrenia. We included 9 patients who met the entry criteria. The results of the quantitative part did not reveal significant changes after the application of active tDCS stimulation in combination with cognitive training. The qualitative part of the study described subjectively perceived changes and...

La douleur neuropathique est fréquente, invalidante et souvent difficile à traiter avec les médicaments dont nous disposons actuellement. Une meilleure compréhension de la physiopathologie de ces douleurs et le développement de nouvelles thérapeutiques sont nécessaires. La stimulation magnétique transcrânienne (TMS) est une technique permettant d’évaluer l’excitabilité corticale et de moduler la douleur et pourrait ainsi constituer une piste intéressante. La sclérose en plaques (SEP) engendre fréquemment des douleurs neuropathiques et constitue la pathologie sur laquelle s’est focalisé ce travail. L’objectif de ce dernier était tout d’abord de définir précisément les caractéristiques des douleurs dans la SEP, ensuite de tester chez des sujets sains de nouvelles fréquences de TMS répétitives (rTMS) pour tenter d’améliorer et de mieux comprendre les effets antalgiques de cette technique et enfin, de réaliser une étude thérapeutique de l’effet de la rTMS chez des patients présentant des douleurs neuropathiques centrales en rapport avec une SEP. Durant la première partie de ce travail, nous avons conduit une enquête postale adressée à 1300 patients SEP qui a permis de montrer que 51% des patients présentaient des douleurs aux caractéristiques neuropathiques, 46% des migraines et que ces deux symptômes n’étaient pas indépendants mais semblaient médiés par des mécanismes distincts. La seconde partie de ce travail a débuté par une revue de la littérature concernant les mécanismes d’action de la rTMS utilisée à visée antalgique. Nous avons ensuite réalisé une étude impliquant 14 sujets sains, qui a permis de montrer qu’une nouvelle fréquence de rTMS, la stimulation theta burst prolongée continue (pcTBS), permettait d’obtenir une antalgie au froid plus importante que la rTMS classique à 10Hz après stimulation du cortex moteur primaire (M1) gauche. Chez ces sujets sains, l’effet antalgique n’était pas lié à une modulation de l’excitabilité du cortex moteur primaire ou à une majoration de la modulation de la douleur induite par une stimulation conditionnante. La dernière partie du travail est en cours. Elle correspond à un essai contrôlé, randomisé, en double aveugle, impliquant 3 groupes parallèles (rTMS à 10Hz, pcTBS et rTMS placebo ciblant le M1 gauche). Soixante-six patients SEP présentant des douleurs neuropathiques réfractaires seront inclus (22 par groupe). Ils bénéficieront d’une séance de rTMS par jour durant cinq jours consécutifs et seront suivis durant un mois. Le critère principal de jugement porte sur la variation de la douleur entre la semaine précédant les rTMS et le huitième jour après la première rTMS. Des objectifs secondaires physiopathologiques (imagerie et excitabilité corticale) impliquent l’inclusion de 40 patients SEP ne présentant pas de douleur (STIMASEP, NCT02059096). / Neuropathic pain is common, debilitating and often difficult to treat with the drugs we currently have. A better understanding of the pathophysiology of these pains and the development of new therapeutics are needed. Transcranial Magnetic Stimulation (TMS) is a technique for evaluating cortical excitability and modulating pain, and could be an interesting avenue. Multiple sclerosis (MS) frequently causes neuropathic pain and is the pathology on which this work has focused. The aim of the latter was first of all to precisely define the characteristics of pain in MS, then to test in healthy subjects new frequencies of repetitive TMS (rTMS) in an attempt to improve and better understand the analgesic effects of this technique and finally, to perform a therapeutic study of the effect of rTMS in patients with central neuropathic pain related to MS.During the first part of this work, we conducted a postal survey addressed to 1300 MS patients, which showed that 51% of patients had pain with neuropathic features, 46% of migraine headaches and that these two symptoms were not independent. but seemed to be mediated by distinct mechanisms.The second part of this work started with a review of the literature concerning the mechanisms of action of rTMS used for analgesic purposes. We then conducted a study involving 14 healthy subjects, which showed that a new frequency of rTMS, prolonged continuous theta-burst stimulation (pcTBS), made it possible to obtain a more important cold-pain treatment than the conventional 10 Hz rTMS. after stimulation of the left primary motor cortex (M1). In these healthy subjects, the analgesic effect was not related to a modulation of the excitability of the primary motor cortex or to an increase in the modulation of pain induced by conditioning stimulation.The last part of the work is in progress. It consists of a randomized, double-blind controlled trial involving 3 parallel groups (10 Hz rTMS, pcTBS and placebo rTMS targeting the left M1). Sixty-six MS patients with refractory neuropathic pain will be included (22 per group). They will receive one rTMS session per day for five consecutive days and will be followed for one month. The primary endpoint is variation in pain between the week prior to rTMS and the eighth day after the first rTMS. Secondary physiopathological objectives (imaging and cortical excitability) imply the inclusion of 40 MS patients presenting no pain (STIMASEP, NCT02059096).

When exploring movement production, motor control researchers have been interested in investigating the relative contributions to different types of movement. In a research setting, a startling acoustic stimulus (SAS) can be used as a tool to explore the neural processes that are occurring when preparing and initiating a movement. Additionally, suprathreshold TMS is another tool which can induce a suppression of the cortical region of the brain, resulting in RT delays which provides us with the ability to assess the corticospinal contributions to a particular movement. The aim of the current study was to investigate potential differences in the planning and execution of bimanual versus unimanual wrist extension movements. It was of particular interest as to whether bimanual coupling occurs at the cortical level or in lower parts of the output pathway (reticulospinal). Participants (N=6) were instructed to complete a unimanual or bimanual wrist extension following a control go-signal or a SAS. For subset of trials, in order to explore the level of corticospinal excitability of the movement, suprathreshold TMS was applied over the left M1 during the task to induce a cortical silent period (CSP). Results revealed that theimpact of TMS on response initiation was not significantly different for unimanual task versus a bimanual task. Furthermore, the SP (silent period) only had an impact on the right limb and not the left during the bilateral task. Lastly, SAS did lead to shorter RTs for both the unimanual and bimanual wrist extension task, but the RT delay induced by TMS in the right limb was not shorter in SAS trials compared to control. The findings of the present study suggest that bimanual coupling may be occurring at the cortical level and in lower parts of the output pathway as there may be correlated neural activity in the two hemispheres occurring during bimanual wrist extension movements.

Schizophrenia is a severe neuropsychiatric disorder characterized by delusions, hallucinations, behavioral symptoms, and cognitive deficits. Roughly, 70%-80% of schizophrenia patients experience auditory verbal hallucinations (AVHs), with 25%-30% demonstrating resistance to conventional antipsychotic medications. Studies suggest a promising role for add-on transcranial direct current stimulation (tDCS) in the treatment of medication-refractory AVHs. The mechanisms through which tDCS could be therapeutic in such cases are unclear, but possibly involve neuroplastic effects. In recent years, functional near-infrared spectroscopy (fNIRS) has been used successfully to study tDCS-induced neuroplastic changes. In a double-blind, sham-controlled design, we applied fNIRS to measure task-dependent cerebral blood flow (CBF) changes as a surrogate outcome of single session tDCS-induced effects on neuroplasticity in a schizophrenia patient with persistent auditory hallucinations. The observations are discussed in this case report.

L’aphasie est un symptôme fréquent après un AVC et a un impact majeur social, économique, médical et psychologique sur les patients. Des études récentes ont tenté avec peu de succès de rechercher des critères pronostiques cliniques précoces de récupération d’une aphasie. L’enjeu de cette possibilité de prédiction est un enjeu majeur clinique et scientifique et peut influencer la prise en charge ré-éducative décidée dès les premiers jours après l’AVC. De plus, l’étude clinico-physiologique de la récupération du langage permettrait de mieux comprendre les mécanismes de plasticité cérébrale mis en jeux. Tout d’abord, nous allons nous intéresser chez le sujet sain à l’implication du cortex moteur dans des tâches de perception, renforçant l’idée que cette structure anatomique jouerait un rôle plus étendu que celui auquel elle a été reléguée pendant de nombreuses années, puis nous allons explorer des facteurs prédictifs de la récupération de l’aphasie, les facteurs langagiers dans un premier temps et des facteurs électrophysiologiques, notamment via la TMS explorant l’intégrité du cortex moteur, et leur contribution dans la prédiction de la récupération. / Considering the high incidence of post-stroke aphasia and its significant social and economic impact, better understanding the mechanisms of language recovery in order to predict patient’s outcome and to optimize rehabilitation is a clinical and scientific challenge. Here we aimed to study whether the motor cortex is involved in speech and language perception, suggesting this structure could play a crucial role. Then, we investigated whether some language features could contribute to the prognosis of aphasia recovery. Finally, we investigated whether the anatomofunctional evaluation of the corticomotor pathway using TMS could improve the prediction of post stroke aphasia recovery.

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Using functional magnetic resonance imaging in humans, Brodmann's area 5 (BA5) is observed to be activated during the suppression of motor output in the context of a NO-GO task. In monkeys, BA5 is associated with somatosensation and specifically linked with motor preparation. The goal of this thesis is to investigate BA5 influences on corticospinal excitability prior to the onset of movement, in the context of a GO/NO-GO paradigm. To achieve this goal, paired-pulse TMS is used to probe the functional connectivity between BA5 and ipsilateral primary motor cortex (M1) for a muscle specific to the hand. Three experiments are performed that investigate the differences in corticospinal output to the hand in a GO task versus a NO-GO task and the stimulation parameters that reveal such differences. Results indicate that BA5 is able to condition M1 prior to movement in a task-specific manner. Further, motor evoked potentials (MEPs) are suppressed in the context of a NO-GO task relative to a GO task, and task-specific differences rely on the intensity and direction of induced current in the cortex. In conclusion, data from this thesis contribute to our understanding of the role of BA5 in motor control. / Thesis / Master of Science in Kinesiology

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