No description available.

No / The right temporoparietal cortex plays a critical role in body representation. Here, we applied repetitive transcranial magnetic stimulation (rTMS) over right extrastriate body area (EBA) and temporoparietal junction (TPJ) to investigate their causative roles in perceptual representations of one's own and others' body. Healthy women adjusted size-distorted pictures of their own body or of the body of another person according to how they perceived the body (subjective task) or how others perceived it (intersubjective task). In keeping with previous reports, at baseline, we found an overall underestimation of body size. Crucially, EBA-rTMS increased the underestimation bias when participants adjusted the images according to how others perceived their own or the other woman's body, suggesting a specific role of EBA in allocentric body representations. Conversely, TPJ-rTMS increased the underestimation bias when participants adjusted the body of another person, either a familiar other or a close friend, in both subjective and intersubjective tasks, suggesting an involvement of TPJ in representing others' bodies. These effects were body-specific, since no TMS-induced modulation was observed when participants judged a familiar object. The results suggest that right EBA and TPJ play active and complementary roles in the complex interaction between the perceptions of one's own and other people's body.

As virtual experiences are rapidly substituting a significant proportion of in-person interactions during the COVID pandemic, it is critical to monitor the effect of screen exposure time on developing children’s behavior and nervous system. Screen use boosts information accessibility and, therefore, may delay the development of the inhibitory control networks in children, who are vulnerable to immediate reward-orientated tendencies and not yet capable of controlling their impulsivity. Therefore, it was hypothesized that as children become more exposed to screens, the development of the inhibitory control network would be delayed and their reward sensitivity will be augmented. Using the ABCD Study Data Repository, 8,334 children’s behavioral and neural data (aged 9-11) were included. Robust mediation analysis and correlation analysis were used to investigate how Screen Time interacts with children’s reward-orientated tendency (e.g. Behavioral approach system, BAS) and the brain's inhibitory network. Intrinsic Frontoparietal Network-Striatum (FPN-Striatum) connectivity strength was used as neural indices of the inhibitory control quality in children. Results showed that Screen Time significantly mediated the relationship between BAS and both waves of the intrinsic inhibitory process. A higher BAS was linked to a longer Screen Time and weaker inhibitory network connectivity. This complete/full mediation model indicates that Screen Time negatively influenced the strength of FPN-Striatum connectivity. In conclusion, the study revealed specific behavioral and neural correlates of screen exposure using a large database, and suggested that increasing screen exposure time may impair the inhibitory capability and increase impulsivity in children. / M.S. / The current study explored the effect of daily screen exposure in pre-adolescent children to provide an important springboard for future work in protecting developing children against the negative impacts of screen use, which has increased significantly during the COVID-19 pandemic. Over 8,000 children’s data from the Adolescent Brain Cognitive Development (ABCD) project was included and found that an increased daily screen exposure time is linked to an inefficient inhibitory control system in the brain. As children’s inhibitory control systems are still developing, this negative effect further hinder the maturation of inhibitory-control systems two years later. Given that the virtual movement is irreversible, the results provide scientific evidence that a balance between screen time and non-screen activities is required for developing children.

Yes / We investigated the role of the human right Supra-Marginal Gyrus (SMG) in the generation of learned eye movement sequences. Using MRI-guided transcranial magnetic stimulation (TMS) we disrupted neural activity in the SMG whilst human observers performed saccadic eye movements to multiple presentations of either predictable or random target sequences. For the predictable sequences we observed shorter saccadic latencies from the second presentation of the sequence. However, these anticipatory improvements in performance were significantly reduced when TMS was delivered to the right SMG during the inter-trial retention periods. No deficits were induced when TMS was delivered concurrently with the onset of the target visual stimuli. For the random version of the task, neither delivery of TMS to the SMG during the inter-trial period nor during the presentation of the target visual stimuli produced any deficit in performance that was significantly different from the no-TMS or control conditions. These findings demonstrate that neural activity within the right SMG is causally linked to the ability to perform short latency predictive saccades resulting from sequence learning. We conclude that neural activity in rSMG constitutes an instruction set with spatial and temporal directives that are retained and subsequently released for predictive motor planning and responses.

A atrite reumatóide é uma doença inflamatória crônica, sem cura, que afeta cerca de 1% da população mundial entre 35 e 65 anos, cujos sinais e sintomas incluem dor, edema, rigidez, degeneração e deformidades articulares. O atual tratamento da artrite reumatóide consiste no uso de drogas anti-reumáticas modificadores de doença (DMARDs), porém são compostos caros e imunossupressivos que podem elevar o risco de infecções graves e malignidades. No presente estudo, analisamos o nervo vago como potencial imunomodulador da inflamação que ocorre na artrite reumatóide experimental. Nossos resultados indicam que a estimulação vagal aferente controla a inflamação articular por meio da ativação de áreas encefálicas simpatoexcitatórias, tais como o núcleo paraventricular do hipotálamo (PVN) e o locus coeruleus (LC). A estimulação do PVN ou do LC diminui a inflamação na articulação, mas somente a integridade do LC foi obrigatória para o controle vagal da inflamação na artrite. A estimulação elétrica cortical direcionada para o córtex parietal ativou o LC e o PVN, mimetizando a ativação vagal, porém induziu um melhor controle da inflamação. Esses resultados sugerem a existência de um mapa encefálico neuroimune capaz de controlar a artrite sem causar efeitos colaterais observáveis. / There is no cure for rheumatoid arthritis affecting over 1% of the world population between 35 e 65 years old suffering chronic inflammation causing pain, swelling, stiffness, degeneration e joint deformities. Disease-modifying anti-rheumatic drugs (DMARDs) are expensive e immunosuppressive, increasing the risk of severe infections e malignancies. Here, we analyzed the potential of the vagus nerve to control experimental arthritic inflammation. Our results indicate that the afferent vagus nerve controls arthritic joint inflammation by activating specific sympatho-excitatory brain areas, such as the paraventricular hypothalamic nucleus (PVN) e the locus coeruleus (LC). PVN or LC stimulation decreased articular inflammation, but only LC integrity was necessary for vagal control of arthritic inflammation. Cortical electrical stimulation above the parietal cortex activated LC e PVN, mimicked vagal activation but induced a better control of arthritic joint inflammation. These results suggest a neuroimmune brain map to control side-specific lateral arthritic joint inflammation without noticeable side effects.

INTRODUÇÃO: A vivência de maus tratos na infância é apontada como um fator de risco para o desenvolvimento de comportamentos antissociais e traços psicopáticos. Estudos sugerem alterações estruturais de substância branca (SB) cerebral em vítimas de maus tratos, que podem estar subjacentes a sintomas psiquiátricos e dificuldades cognitivas. OBJETIVO: Investigar o comportamento social de adolescentes vítimas de maus tratos (A-VMT), através da comparação de suas habilidades sociais e traços de psicopatia com um grupo controle (GC), e de possíveis correlações destas medidas com os diferentes tipos de maus tratos e com o volume de SB cerebral. MÉTODO: Foram avaliados 67 A-VMT e 41 adolescentes do GC através do Questionário de Traumas na Infância (QUESI), da Psychopathy Checklist Youth Version (PCL-YV) e do Inventário de Habilidades Sociais para Adolescentes (IHSA). Também foram adquiridas imagens anatômicas cerebrais através de equipamento de ressonância magnética (1,5T Siemens Sonata) e realizadas análises de morfometria baseada em voxels (VBM). RESULTADOS: Os A-VMT apresentaram maior intensidade de traços psicopáticos e mais déficits de habilidades sociais que o GC. A negligência emocional foi a forma de maus tratos que mais influenciou a presença de traços de psicopatia e que mais associou-se a prejuízos de habilidades sociais específicas. O volume de SB de regiões do hemisfério esquerdo (giro angular, precuneus e lobo parietal inferior) correlacionouse negativamente com o fator afetivo da PCL:YV. Além disso, foram encontradas correlações positivas entre o volume de SB de regiões de hemisfério direito com fatores de psicopatia: o volume do lobo parietal superior direito correlacionou-se com características interpessoais e o do giro pré-central com o fator antissocial. CONCLUSÃO: Os A-VMT apresentaram déficits do comportamento social quando comparados ao GC. O volume de SB de áreas cerebrais envolvidas no processamento de informações sociais e reconhecimento de emoções se correlacionou com traços específicos da psicopatia. A vivencia de maus tratos na infância pode contribuir para déficits na cognição social, o que por sua vez, pode predispor esta vulnerável população a alguns comportamentos antissociais / Introduction: Child maltreatment is considered a risk factor for the development of antisocial behaviors and psychopathic traits. Studies suggest that specific white matter tracts may be vulnerable to child maltreatment and their alterations can be associated with psychiatric symptoms and cognitive deficits. Aim: Compare social skills and psychopathic traits between maltreated adolescents (MTA) and a control group, as well as their possible correlations with different types of maltreatment and white matter volumes.. Method: The sample was composed by 67 MTA and 41 youths from the CG. Brain images were acquired by magnetic resonance imaging equipment (1,5T Siemens Sonata) for voxel-based morphometry analyses. The clinical evaluation was carried out using Childhood Trauma Inventory (CTQ), Social Skills Inventory for Adolescents (SSIA) and The Hare Psychopathy Checklist: Youth Version (PCL:YV). Results: MTA presented more psychopathic traits and social skills deficits than the CG. Emotional neglect was the only maltreatment subtype with significant effect on psychopathic traits, and it was correlated with specific social skills deficits. The white matter volumes of left hemisphere regions (angular gyrus, precuneus and inferior parietal lobe) were negatively correlated with PCL:YV affective factor scores. Moreover, positive correlations between white matter volume of right hemisphere areas (superior parietal lobe and precentral gyrus) and specific psychopathic traits (antisocial and interpersonal) were found. Conclusion: MTA presented social deficits when compared to CG. The white matter volume of brain areas associated with social information processing and emotion recognition was correlated with specific psychopathic traits. Child maltreatment may contribute to social cognition deficits and predispose this vulnerable population to psychopathic traits

INTRODUÇÃO: A vivência de maus tratos na infância é apontada como um fator de risco para o desenvolvimento de comportamentos antissociais e traços psicopáticos. Estudos sugerem alterações estruturais de substância branca (SB) cerebral em vítimas de maus tratos, que podem estar subjacentes a sintomas psiquiátricos e dificuldades cognitivas. OBJETIVO: Investigar o comportamento social de adolescentes vítimas de maus tratos (A-VMT), através da comparação de suas habilidades sociais e traços de psicopatia com um grupo controle (GC), e de possíveis correlações destas medidas com os diferentes tipos de maus tratos e com o volume de SB cerebral. MÉTODO: Foram avaliados 67 A-VMT e 41 adolescentes do GC através do Questionário de Traumas na Infância (QUESI), da Psychopathy Checklist Youth Version (PCL-YV) e do Inventário de Habilidades Sociais para Adolescentes (IHSA). Também foram adquiridas imagens anatômicas cerebrais através de equipamento de ressonância magnética (1,5T Siemens Sonata) e realizadas análises de morfometria baseada em voxels (VBM). RESULTADOS: Os A-VMT apresentaram maior intensidade de traços psicopáticos e mais déficits de habilidades sociais que o GC. A negligência emocional foi a forma de maus tratos que mais influenciou a presença de traços de psicopatia e que mais associou-se a prejuízos de habilidades sociais específicas. O volume de SB de regiões do hemisfério esquerdo (giro angular, precuneus e lobo parietal inferior) correlacionouse negativamente com o fator afetivo da PCL:YV. Além disso, foram encontradas correlações positivas entre o volume de SB de regiões de hemisfério direito com fatores de psicopatia: o volume do lobo parietal superior direito correlacionou-se com características interpessoais e o do giro pré-central com o fator antissocial. CONCLUSÃO: Os A-VMT apresentaram déficits do comportamento social quando comparados ao GC. O volume de SB de áreas cerebrais envolvidas no processamento de informações sociais e reconhecimento de emoções se correlacionou com traços específicos da psicopatia. A vivencia de maus tratos na infância pode contribuir para déficits na cognição social, o que por sua vez, pode predispor esta vulnerável população a alguns comportamentos antissociais / Introduction: Child maltreatment is considered a risk factor for the development of antisocial behaviors and psychopathic traits. Studies suggest that specific white matter tracts may be vulnerable to child maltreatment and their alterations can be associated with psychiatric symptoms and cognitive deficits. Aim: Compare social skills and psychopathic traits between maltreated adolescents (MTA) and a control group, as well as their possible correlations with different types of maltreatment and white matter volumes.. Method: The sample was composed by 67 MTA and 41 youths from the CG. Brain images were acquired by magnetic resonance imaging equipment (1,5T Siemens Sonata) for voxel-based morphometry analyses. The clinical evaluation was carried out using Childhood Trauma Inventory (CTQ), Social Skills Inventory for Adolescents (SSIA) and The Hare Psychopathy Checklist: Youth Version (PCL:YV). Results: MTA presented more psychopathic traits and social skills deficits than the CG. Emotional neglect was the only maltreatment subtype with significant effect on psychopathic traits, and it was correlated with specific social skills deficits. The white matter volumes of left hemisphere regions (angular gyrus, precuneus and inferior parietal lobe) were negatively correlated with PCL:YV affective factor scores. Moreover, positive correlations between white matter volume of right hemisphere areas (superior parietal lobe and precentral gyrus) and specific psychopathic traits (antisocial and interpersonal) were found. Conclusion: MTA presented social deficits when compared to CG. The white matter volume of brain areas associated with social information processing and emotion recognition was correlated with specific psychopathic traits. Child maltreatment may contribute to social cognition deficits and predispose this vulnerable population to psychopathic traits

A atrite reumatóide é uma doença inflamatória crônica, sem cura, que afeta cerca de 1% da população mundial entre 35 e 65 anos, cujos sinais e sintomas incluem dor, edema, rigidez, degeneração e deformidades articulares. O atual tratamento da artrite reumatóide consiste no uso de drogas anti-reumáticas modificadores de doença (DMARDs), porém são compostos caros e imunossupressivos que podem elevar o risco de infecções graves e malignidades. No presente estudo, analisamos o nervo vago como potencial imunomodulador da inflamação que ocorre na artrite reumatóide experimental. Nossos resultados indicam que a estimulação vagal aferente controla a inflamação articular por meio da ativação de áreas encefálicas simpatoexcitatórias, tais como o núcleo paraventricular do hipotálamo (PVN) e o locus coeruleus (LC). A estimulação do PVN ou do LC diminui a inflamação na articulação, mas somente a integridade do LC foi obrigatória para o controle vagal da inflamação na artrite. A estimulação elétrica cortical direcionada para o córtex parietal ativou o LC e o PVN, mimetizando a ativação vagal, porém induziu um melhor controle da inflamação. Esses resultados sugerem a existência de um mapa encefálico neuroimune capaz de controlar a artrite sem causar efeitos colaterais observáveis. / There is no cure for rheumatoid arthritis affecting over 1% of the world population between 35 e 65 years old suffering chronic inflammation causing pain, swelling, stiffness, degeneration e joint deformities. Disease-modifying anti-rheumatic drugs (DMARDs) are expensive e immunosuppressive, increasing the risk of severe infections e malignancies. Here, we analyzed the potential of the vagus nerve to control experimental arthritic inflammation. Our results indicate that the afferent vagus nerve controls arthritic joint inflammation by activating specific sympatho-excitatory brain areas, such as the paraventricular hypothalamic nucleus (PVN) e the locus coeruleus (LC). PVN or LC stimulation decreased articular inflammation, but only LC integrity was necessary for vagal control of arthritic inflammation. Cortical electrical stimulation above the parietal cortex activated LC e PVN, mimicked vagal activation but induced a better control of arthritic joint inflammation. These results suggest a neuroimmune brain map to control side-specific lateral arthritic joint inflammation without noticeable side effects.

Au cours de ma thèse, je me suis principalement intéressée aux interactions entre les systèmes angiotensine et gluco-minéralocorticoïde dans la paroi artérielle et particulièrement dans la physiopathologie du remodelage artériel. Pour cela, nous avons étudié les mécanismes moléculaires aboutissant au développement de l’athérome et qui impliqueraient ces deux systèmes. Notre hypothèse est qu’un excès local en gluco-et/ou minéralocorticoïdes dans la paroi favorise le développement de l’athérome en stimulant le système angiotensine. Nos résultats ont confirmé l’expression des éléments nécessaires à la synthèse et à l'action des gluco-minéralocorticoïdes dans la paroi carotidienne humaine et dans les CMLV, avec une prévalence de la voie des glucocorticoïdes. Cette prédominance se manifeste par l’effet stimulant du cortisol sur l’expression des marqueurs des processus fibrosants, lipogéniques et inflammatoire mis en jeu lors de la formation de l’athérome. La relation entre le taux d’expression pariétale de GRα et 11β-HSD1 d’une part et le collagène 1 d’autre part suggère une contribution majeure des glucocorticoïdes dans la rigidité artérielle. Il a également été observé que le cortisol a un effet stimulant sur l’expression du collagène dans les CMLV suggérant ainsi que le cortisol favoriserait la survenue des accidents cardiovasculaires. La relation inverse entre le taux d’expression pariétal de GRα et la mesure de la pression artérielle diastolique est en faveur de cette hypothèse. De même, l’augmentation du taux de l’ARNm de GRα chez les patients ayant fait un accident cardiovasculaire corrobore l’hypothèse d’un rôle délétère des glucocorticoïdes dans le remodelage athéromateux. Nos résultats montrent que le système glucocorticoïde est un puissant stimulateur du système angiotensine pariétal et suggère l’existence d’une régulation commune de la synthèse de l’angiotensine II, de l’aldostérone et du cortisol évoquant ainsi la possibilité d’interactions entre les systèmes angiotensine et gluco-minéralocorticoïde pariétaux. Par ailleurs, les concentrations basses du cortisol plasmatique chez les patients traités par des bloqueurs du système rénine angiotensine est en faveur de la théorie d’amplification mutuelle des systèmes angiotensine et glucocorticoïde. Notre étude souligne l’intérêt des bloqueurs du SRA comme approche thérapeutique préférentielle à utiliser afin d’atténuer les effets délétères du cortisol, améliorer le risque cardiovasculaire et le pronostic des patients / The involvement of the renin angiotensin system, cortisol and aldosterone in the increase of cardiovascular risk is well known as well as some of relationships between RAS and corticosteroids but their interactions within arterial wall and particularly during atheroma formation are not established. Considering all these data, we hypothesize that an increase in local gluco-and/or mineralocorticoid synthesis and activity within the arterial wall may favour atheroma development by stimulating tissue angiotensin system. Our results give argument in favour of an independence betweenthe parietal and endocrine corticosteroid systems. We have shown the prevailing involvement of the glucocorticoid pathway in the atherosclerotic remodelling both in terms of intra-parietal expression and regulation of fibrotic, inflammatory and lipogenic effects in VSMCs together with the further amplification of this involvement after adipocyte dedifferentiation of VSMCs. There is modulation of GR and MR effects with a change in the cell pathophysiological state. Interestingly, there is no “illicit” cortisol-dependent activation of MR-receptor. We conclude that cortisol involvement in atheroma formation could pass apart from its continuing stimulating effect on its own synthesis and action, through mutual stimulating effects of cortisol and angiotensin II on their reciprocal compounds. These processes could already take place at the initial stage of atheroma and might intensify as the atheroma development progresses. The up-regulation of parietal angiotensin system could be revealed by a low plasma renin. The lower plasma cortisol levels in patients on RAS blocker treatment corroborates the thesis of mutual amplification of effects between glucocorticoids and angiotensin system, and this treatment would be particularly beneficial in essential hypertensive patients with low plasma renin, to attenuate both angiotensin II and also cortisol up-regulation

Der menschliche inferiore Parietallappen (IPC) gehört zum Assoziationskortex und spielt eine wichtige Rolle bei der Integration von somatosensorischen (taktilen), visuellen und akustischen Reizen. Bisher gibt es keine eindeutigen Informationen über den strukturellen Aufbau dieser Hirnregion. Parzellierungen anhand der Zytoarchitektur reichen von zwei (Brodmann 1909) bis sieben Subareale (Caspers et al. 2006). Homologien zwischen dem IPC des Menschen und Makaken-Affen sind weitestgehend unbekannt. In der vorliegenden Arbeit wurden der Aufbau und die Konnektivitäten des menschlichen IPC genauer untersucht. Dazu führte man eine konnektivitätsbasierte Parzellierung des IPC an 20 Probanden durch. Als Methode kam Diffusions-Tensor-Imaging (DTI) kombiniert mit probabilistischer Traktogra-phie zum Einsatz. Der IPC konnte anhand der Konnektivitäten in drei Subareale (IPCa, IPCm, IPCp) parzelliert werden. Diese besitzen in beiden Hemisphären eine ähnliche Größe und eine rostro-kaudale Anordnung. Die Parzellierung ist vergleichbar mit der des Makaken-IPC, bei dem ebenfalls eine Unterteilung in drei Areale (PF, PFG, PG) und eine rostro-kaudale Anordnung nachgewiesen werden konnte. Jedes Subareal des menschlichen IPC besitzt ein individuelles Konnektivitätsmuster. Beim Menschen als auch beim Makaken gibt es starke Verbindungen zum lateralen prämotorischen Kortex und zum superioren Parietallappen. Diese Gemeinsamkeiten lassen darauf schließen, dass strukturelle Eigenschaften im Laufe der Evolution erhalten geblieben sind. Allerdings sind beim Menschen auch Neuentwicklungen nachweisbar. Dazu gehören die deutlich hervortretenden Verbindungen zum Temporallappen. Möglicherweise haben sich diese erst während der Evolution entwickelt und sind beim Menschen als Teil des perisylvischen Sprachnetzwerkes an der Sprachbildung beteiligt.:1. Einleitung 1.1. Der inferiore Parietalkortex 1.2. Konnektivitätsbasierte-Parzellierung durch Diffusions-Tensor-Bildgebung 1.3. Motivation 1.4. Überblick 2. Methoden 2.1. Theoretische Grundlagen 2.1.1. Magnet-Resonanz-Bildgebung 2.1.2. Diffusionsgewichtete Magnet-Resonanz-Tomographie 2.1.3. Diffusions-Tensor-Bildgebung 2.1.4. Traktographie in der weißen Substanz 2.1.5. Parzellierungsmethoden 2.2. Datenerfassung 2.3. Datenverarbeitung 2.4. Parzellierung des IPC 2.4.1. Definition der Analyseregion 2.4.2. Bestimmung der Startvoxel 2.4.3. Probabilistische Traktographie 2.4.4. Clustering 2.4.5. Populationskarte 2.4.6. Statistische Auswertung der Parzellierungsergebnisse 2.5. Analyse der Konnektivitäten des IPC 2.5.1. Berechnung der Konnektivitäten 2.5.2. Statistische Auswertung der Konnektivitäten 3. Ergebnis 3.1. Definition der Analyseregion 3.2. Analyse der Parzellierung 3.3. Statistische Auswertung der Parzellierung 3.4. Zusammenfassung der Parzellierungsergebnisse 3.5. Populationskarte aller Probanden 3.6. Statistische Auswertung weiterer Eigenschaften 3.6.1. Schwerpunkte der Areale 3.6.2. Größe der Areale 3.7. Analyse der Konnektivitäten 3.8. Statistische Auswertung der Konnektivitäten 3.9. Vergleich der linken und rechten Hemisphäre 4. Diskussion 4.1. Zwei oder drei Regionen: Welche Parzellierung ist am geeignetsten für den IPC? 4.2. Welche Konnektivitäten charakterisieren den IPC? 4.3. Vergleich von Mensch und Makaken 4.3.1. Homologien in der Parzellierung des IPC 4.3.2. Homologien in den Konnektivitäten des IPC 4.4. Funktionelle Bedeutung der IPC Parzellierung 4.4.1. Der IPC des Makaken 4.4.2. Der IPC des Menschen 4.5. Anmerkung zu den Methoden 4.5.1. Definition der Analyseregion 4.5.2. Auflösung der Diffusions-Tensor-Bildgebung 4.5.3. Traktographie Artefakte 4.6. Zusammenfassung 5. Anhang 5.1. Glossar 5.2. Abkürzungsverzeichnis 5.3. Detaillierte Abbildung der Ergebnisse 6. Danksagung 7. Zusammenfassung der Arbeit 8. Literaturverzeichnis 9. Publikation 10. Eigenständigkeitserklärung 11. Lebenslauf / The human inferior parietal cortex convexity (IPCC) is an important association area, which integrates auditory, visual and somatosensory information. However, the structural organization of the IPCC is a controversial issue. For example, cytoarchitectonic parcellations reported in the literature range from two to seven areas. Moreover, anatomical descriptions of the human IPCC are often based on experiments in the macaque monkey. In this study we used diffusion-weighted magnetic resonance imaging (dMRI) combined with probabilistic tractography to quantify the connectivity of the human IPCC, and used this information to parcellate this cortex area. This provides a new structural map of the human IPCC, comprising three sub-areas (IPCa, IPCm, IPCp) of comparable size, in a rostro-caudal arrangement in the left and right hemisphere. Each sub-area is characterized by a connectivity fingerprint and the parcellation is similar to the subdivision reported for the macaque IPCC (rostro-caudal areas areas PF, PFG, and PG). However, the present study also reliably demonstrates new structural features in the connectivity pattern of the human IPCC, which are not known to exist in the macaque. This study quantifies inter-subject variability by providing a population representation of the sub-area arrangement, and demonstrates substantial lateralization of the connectivity patterns of IPCC.:1. Einleitung 1.1. Der inferiore Parietalkortex 1.2. Konnektivitätsbasierte-Parzellierung durch Diffusions-Tensor-Bildgebung 1.3. Motivation 1.4. Überblick 2. Methoden 2.1. Theoretische Grundlagen 2.1.1. Magnet-Resonanz-Bildgebung 2.1.2. Diffusionsgewichtete Magnet-Resonanz-Tomographie 2.1.3. Diffusions-Tensor-Bildgebung 2.1.4. Traktographie in der weißen Substanz 2.1.5. Parzellierungsmethoden 2.2. Datenerfassung 2.3. Datenverarbeitung 2.4. Parzellierung des IPC 2.4.1. Definition der Analyseregion 2.4.2. Bestimmung der Startvoxel 2.4.3. Probabilistische Traktographie 2.4.4. Clustering 2.4.5. Populationskarte 2.4.6. Statistische Auswertung der Parzellierungsergebnisse 2.5. Analyse der Konnektivitäten des IPC 2.5.1. Berechnung der Konnektivitäten 2.5.2. Statistische Auswertung der Konnektivitäten 3. Ergebnis 3.1. Definition der Analyseregion 3.2. Analyse der Parzellierung 3.3. Statistische Auswertung der Parzellierung 3.4. Zusammenfassung der Parzellierungsergebnisse 3.5. Populationskarte aller Probanden 3.6. Statistische Auswertung weiterer Eigenschaften 3.6.1. Schwerpunkte der Areale 3.6.2. Größe der Areale 3.7. Analyse der Konnektivitäten 3.8. Statistische Auswertung der Konnektivitäten 3.9. Vergleich der linken und rechten Hemisphäre 4. Diskussion 4.1. Zwei oder drei Regionen: Welche Parzellierung ist am geeignetsten für den IPC? 4.2. Welche Konnektivitäten charakterisieren den IPC? 4.3. Vergleich von Mensch und Makaken 4.3.1. Homologien in der Parzellierung des IPC 4.3.2. Homologien in den Konnektivitäten des IPC 4.4. Funktionelle Bedeutung der IPC Parzellierung 4.4.1. Der IPC des Makaken 4.4.2. Der IPC des Menschen 4.5. Anmerkung zu den Methoden 4.5.1. Definition der Analyseregion 4.5.2. Auflösung der Diffusions-Tensor-Bildgebung 4.5.3. Traktographie Artefakte 4.6. Zusammenfassung 5. Anhang 5.1. Glossar 5.2. Abkürzungsverzeichnis 5.3. Detaillierte Abbildung der Ergebnisse 6. Danksagung 7. Zusammenfassung der Arbeit 8. Literaturverzeichnis 9. Publikation 10. Eigenständigkeitserklärung 11. Lebenslauf