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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.

INTRODUCTION:Whirligig beetles (Coleoptera: Gyrinidae) are aquatic insects living on the water surface. They are equipped with four compound eyes, an upper pair viewing above the water surface and a lower submerged pair viewing beneath the water surface, but little is known about how their visual brain centers (optic lobes) are organized to serve such unusual eyes. We show here, for the first time, the peculiar optic lobe organization of the larval and adult whirligig beetle Dineutus sublineatus.RESULTS:The divided compound eyes of adult whirligig beetles supply optic lobes that are split into two halves, an upper half and lower half, comprising an upper and lower lamina, an upper and lower medulla and a bilobed partially split lobula. However, the lobula plate, a neuropil that in flies is known to be involved in mediating stabilized flight, exists only in conjunction with the lower lobe of the lobula. We show that, as in another group of predatory beetle larvae, in the whirligig beetle the aquatic larva precociously develops a lobula plate equipped with wide-field neurons. It is supplied by three larval laminas serving the three dorsal larval stemmata, which are adjacent to the developing upper compound eye.CONCLUSIONS:In adult whirligig beetles, dual optic neuropils serve the upper aerial eyes and the lower subaquatic eyes. The exception is the lobula plate. A lobula plate develops precociously in the larva where it is supplied by inputs from three larval stemmata that have a frontal-upper field of view, in which contrasting objects such as prey items trigger a body lunge and mandibular grasp. This precocious lobula plate is lost during pupal metamorphosis, whereas another lobula plate develops normally during metamorphosis and in the adult is associated with the lower eye. The different roles of the upper and lower lobula plates in supporting, respectively, larval predation and adult optokinetic balance are discussed. Precocious development of the upper lobula plate represents convergent evolution of an ambush hunting lifestyle, as exemplified by the terrestrial larvae of tiger beetles (Cicindelinae), in which activation of neurons in their precocious lobula plates, each serving two large larval stemmata, releases reflex body extension and mandibular grasp.

Theoretical models of information storage in the brain have suggested that neurons may undergo an experience-dependent tuning or sharpening of their representations in order to maximize the amount of information that can be stored. Changes in the tuning profiles of neurons have been demonstrated to occur when animals must learn perceptual discriminations, however, whether similar changes occur in the absence of behavioral demands is unclear. To address these questions, the activity of simultaneously recorded medial temporal lobe (MTL) neurons was studied in relation to a passive visual recognition memory task. The structure of this task was such that it allowed for a comparison between novelty related responses as well as tuning properties of individual neurons. A total of 565 well isolated single neurons were recorded. The first contribution of this dissertation is the finding of a dissociation between different medial temporal lobe regions such that neurons in temporal area F (TF), but not perirhinal cortex (PRC) or the hippocampus, show an experience-dependent change in their stimulus selectivity. This finding indicates that tuning of stimulus representations may be an effective mechanism for maximizing information storage in some brain regions. The absence of stimulus tuning in higher level association regions (i.e. TF and PRC) suggests that tuning in these regions may be disadvantageous due to the need to construct unified representations across sensory modalities. A complimentary question to the question of network storage capacity is how networks avoid saturation in the connections between neurons. The second contribution of this dissertation is the finding that there exists a decrease in the magnitude of the short time scale correlations between pairs of neurons; suggesting that networks reduce the number of connections between neurons as a stimulus becomes familiar. Gamma oscillations have been proposed to be the mechanism by which groups of neurons coordinate their activity. However, network coordination has only been indirectly measured. The final contribution of this dissertation is the finding that the magnitude of gamma oscillations is strongly correlated with enhanced magnitude of correlations between neurons.

It is well established that patients with temporal lobe epilepsy (TLE) commonly report memory difficulties. The aim of this thesis was to use a novel approach adopting Nelson & Narens' (1990) theoretical framework to investigate whether metacognitive knowledge and memory performance were differentially disrupted in patients with TLE. More specifically, investigating to what extent poor memory in TLE could result from inadequate metamemory monitoring, inadequate metamemory control or both. Experiment I employed a combined Judgement-of-Learning and Feeling-of-Knowing task to investigate whether participants could monitor their memory successfully at both the item-by-item and global levels. The results revealed a dissociation between memory and metamemory in TLE patients. TLE patients presented with a clear episodic memory deficit compared with controls yet preserved metamemory abilities. Experiments 2 and 3 explored the sensitivity approach to examine metacognitive processes that operate during encoding in TLE patients and controls. Both these experiments demonstrated that TLE patients were sensitive to monitoring and control processes at encoding. The final experiment further investigated memory performance by examining the role of lateralisation of the seizure focus using material specific information and the 'Remember-Know' paradigm. The findings from the verbal task provided partial support to the material-specific hypothesis. The results from these experiments are discussed in terms of their association with executive functioning and memory deficits in TLE, and have important implications for future research examining memory and metamemory in TLE patients and other clinical populations.

<p>Temporal lobe epilepsy is a common and devastating disorder that features recurrent seizures and is often associated with pathologic anxiety and hippocampal sclerosis. An episode of prolonged seizures (status epilepticus) is thought to promote development of human temporal lobe epilepsy years later. A chemical-genetic approach established proof of concept that transiently inhibiting the receptor tyrosine kinase, TrkB, following status epilepticus prevented epilepsy, anxiety-like behavior and hippocampal damage in a mouse model, providing rationale for developing a therapeutic targeting TrkB signaling. To circumvent the undesirable consequence that global inhibition of TrkB exacerbates neuronal degeneration following status epilepticus, we sought to identify both the TrkB-activated signaling pathway mediating these pathologies and a compound that uncouples TrkB from the responsible signaling effector. To accomplish these goals, we used genetically modified mice and a model of seizures and epilepsy induced by a chemoconvulsant. Genetic inhibition of TrkB-mediated phospholipase C gamma 1 (PLC gamma 1) signaling suppressed seizures induced by a chemoconvulsant, leading to design of a peptide (pY816) that inhibited the interaction of TrkB with PLC gamma 1. We demonstrate that pY816 selectively inhibits TrkB-mediated activation of PLC gamma 1 both in vitro and in vivo. Treatment with pY816 prior to administration of a chemoconvulsant suppressed seizures in a dose- and time-dependent manner. Treatment with pY816 initiated after chemoconvulsant-evoked status epilepticus and continued for just three days suppressed seizure-induction of epilepsy, anxiety-like behavior and hippocampal damage assessed months later. This study elucidates the signaling pathway by which TrkB activation produces diverse neuronal activity-driven pathologies and demonstrates therapeutic benefits of an inhibitor of this pathway in an animal model in vivo. A strategy of uncoupling a receptor tyrosine kinase from a signaling effector may prove useful in diverse diseases in which excessive receptor tyrosine kinase signaling contributes.</p> / Dissertation

Introdução: A epilepsia é uma doença de grande relevância médica e social, trazendo grande impacto aos pacientes e a sociedade como um todo. A Epilepsia do Lobo Temporal Mesial (ELTM) é a epilepsia refratária mais prevalente, tendo em sua causalidade o impacto do desequilíbrio entre circuitos neuronais excitatórios e inibitórios, necessitando da remoção cirúrgica das estruturas alteradas e da interrupção das suas vias para melhor controle das crises e qualidade de vida dos pacientes. Objetivo: Buscando ampliar o esclarecimento do papel da amígdala junto as modificações intrínsecas nos receptores de neurotransmissores e em suas subunidades nos mecanismos de ictogênese e epileptogênese, possibilitando o aprimoramento das técnicas cirúrgicas atualmente empregadas, além de novas modalidades terapêuticas, o presente estudo analisou as expressões gênicas das subunidades de receptores excitatórios, NMDA (NR2C e NR3A, genes GRIN2C e GRIN3A), Cainato (GluK1 e GluK2, genes GRIK1 e GRIK2), e subunidade de receptor inibitório GABAA (?4 e ?5, genes GABRA4 e GABRA5) e subtipos de receptor de neuropeptídio Y (Y2 e Y5, com genes NPY2R e NPY5R), em núcleos basolaterais de amígdalas humanas de pacientes com ELTM. Material e Métodos: Foram utilizados fragmentos de amígdala de 20 pacientes que fizeram amigdalohipocampectomia junto ao Serviço de Neurocirurgia do HC-FMRP-USP, sendo 10 pacientes com controle efetivo pós-operatório (Engel 1) e 10 pacientes com controle inadequado das crises(Engel 3 e 4), 10 amígdalas obtidas de autópsias (controle), utilizando a qPCR. Resultados: Foram evidenciadas diferenças da expressão nas subunidades NR2C (p=0,006) e ?4 do GABAAr (p=0,008), subtipo de NPYr Y2(p=0.013), com tendência junto a subunidade NR3A(p=0,077). Não evidenciando significância estatísticas nas análises das subunidades GluK1(p=0,147), GluK2(p=0,182) e?5 do GABAAr (p=0,272), para o subtipo NPYr Y1(p=0,242). Conclusão: As análises sugerem diferenças na expressão de receptores de neurotransmissores em pacientes com epilepsia em relação ao controle contendo as subunidadeNR2C e ?4 do GABAAr, com tendências a subunidade NR3A, indicando modificações neuronais amigdalianas possivelmente envolvidas com a zona epileptogênica, possibilitando aprimoramentos terapêuticos junto ao tratamento dasepilepsias refratárias. Também podemos inferir que os mecanismos neuronais envolvendo as subunidades?4 doGABAAr e GRIN2C, e do subtipo Y2 do NPYr na epileptogênese e ictogênese da ELTM podem ser semelhantes entre amígdala e hipocampo, enquanto os envolvendo as subunidades GLUK1 e GLUK2 parecem ser diferenciados; o gene GABRA5 pode ser utilizado como gene de controle endógeno em estudos com amigdala e hipocampo na ELTM. / Introduction: Epilepsy is a disease whith highly medical and social relevance, bringing impact on patients and society as a whole. Mesial Temporal Lobe Epilepsy (MTLE) is the most prevalent refractory epilepsy, in its causality the impact of the imbalance between excitatory neuronal circuits and inhibitory, needing a surgical removal of the altered structures and the interruption of their way to better seizure control and quality of life pacientes. Goal: Searching to increase understanding the role of the amygdala with intrinsic changes in neurotransmitter receptors and their subunits in ictogenesis mechanisms and epileptogenesis, enabling the improvement of surgical techniques currently used, as well as new therapeutic modalities, this study analyzed gene expression on the subunits of excitatory receptors, NMDA (NR2 and NR3A, GRIN2C and GRIN3A genes) and kainate (GluK1 and GluK2, GRIK1 and GRIK2 genes), and inhibitory receptor subunit GABA (?4 and ?5, genes GABRA4 and GABRA5 ), neuropeptide Y receptor subtypes (Y2 and Y5, and NPY5R with NPY2R gene) in the basolateral nucleus of human amygdala of patients with MTLE. Material and Methods: Amygdala fragments were used in 20 patients who made amigdalohipocampectomia with the Service neurosurgery HC-FMRP-USP, 10 patients with postoperative effective control (Engel 1) and 10 patients with inadequate control of seizures (Engel 3:04), and 10 amygdalas obtained from autopsies (control) using qPCR. Results: Were differences evidenced expression in NR2C subunits (p = 0.006) e?4 the GABAAr (p = 0.008), and subtype NPYr Y2 (p = 0.013), along with a tendency of NR3A subunits (p = 0.077). Showing no statistical significance in the analysis of GluK1 subunits (p = 0.147), GluK2 (p = 0.182) e?5 the GABAAr (p = 0.272), and the NPYr Y1 subtype (p = 0.242). Conclusion: The analyzes suggest differences in expression of neurotransmitter receptors in epilepsy patients on control containing the NR2C subunits and ?4 of GABAAr with NR3A subunits trends indicating amygdala neuronal modifications possibly involved in the epileptogenic zone, enabling therapeutic improvements with the refractory epilepsy treatment. As well can infer that the neural mechanisms involving the subunits ?4 GABAAr, GRIN2C and Y2 NPYr subtype in epileptogenesis and ictogenesis of TLE can be similar between the amygdala and hippocampus, while involving GLUK1 and GLUK2 subunits appear to be different; the GABRA5 gene can be used as endogenous control gene in studies of hippocampus and amygdala in TLE.

Introdução: A epilepsia é uma doença de grande relevância médica e social, trazendo grande impacto aos pacientes e a sociedade como um todo. A Epilepsia do Lobo Temporal Mesial (ELTM) é a epilepsia refratária mais prevalente, tendo em sua causalidade o impacto do desequilíbrio entre circuitos neuronais excitatórios e inibitórios, necessitando da remoção cirúrgica das estruturas alteradas e da interrupção das suas vias para melhor controle das crises e qualidade de vida dos pacientes. Objetivo: Buscando ampliar o esclarecimento do papel da amígdala junto as modificações intrínsecas nos receptores de neurotransmissores e em suas subunidades nos mecanismos de ictogênese e epileptogênese, possibilitando o aprimoramento das técnicas cirúrgicas atualmente empregadas, além de novas modalidades terapêuticas, o presente estudo analisou as expressões gênicas das subunidades de receptores excitatórios, NMDA (NR2C e NR3A, genes GRIN2C e GRIN3A), Cainato (GluK1 e GluK2, genes GRIK1 e GRIK2), e subunidade de receptor inibitório GABAA (?4 e ?5, genes GABRA4 e GABRA5) e subtipos de receptor de neuropeptídio Y (Y2 e Y5, com genes NPY2R e NPY5R), em núcleos basolaterais de amígdalas humanas de pacientes com ELTM. Material e Métodos: Foram utilizados fragmentos de amígdala de 20 pacientes que fizeram amigdalohipocampectomia junto ao Serviço de Neurocirurgia do HC-FMRP-USP, sendo 10 pacientes com controle efetivo pós-operatório (Engel 1) e 10 pacientes com controle inadequado das crises(Engel 3 e 4), 10 amígdalas obtidas de autópsias (controle), utilizando a qPCR. Resultados: Foram evidenciadas diferenças da expressão nas subunidades NR2C (p=0,006) e ?4 do GABAAr (p=0,008), subtipo de NPYr Y2(p=0.013), com tendência junto a subunidade NR3A(p=0,077). Não evidenciando significância estatísticas nas análises das subunidades GluK1(p=0,147), GluK2(p=0,182) e?5 do GABAAr (p=0,272), para o subtipo NPYr Y1(p=0,242). Conclusão: As análises sugerem diferenças na expressão de receptores de neurotransmissores em pacientes com epilepsia em relação ao controle contendo as subunidadeNR2C e ?4 do GABAAr, com tendências a subunidade NR3A, indicando modificações neuronais amigdalianas possivelmente envolvidas com a zona epileptogênica, possibilitando aprimoramentos terapêuticos junto ao tratamento dasepilepsias refratárias. Também podemos inferir que os mecanismos neuronais envolvendo as subunidades?4 doGABAAr e GRIN2C, e do subtipo Y2 do NPYr na epileptogênese e ictogênese da ELTM podem ser semelhantes entre amígdala e hipocampo, enquanto os envolvendo as subunidades GLUK1 e GLUK2 parecem ser diferenciados; o gene GABRA5 pode ser utilizado como gene de controle endógeno em estudos com amigdala e hipocampo na ELTM. / Introduction: Epilepsy is a disease whith highly medical and social relevance, bringing impact on patients and society as a whole. Mesial Temporal Lobe Epilepsy (MTLE) is the most prevalent refractory epilepsy, in its causality the impact of the imbalance between excitatory neuronal circuits and inhibitory, needing a surgical removal of the altered structures and the interruption of their way to better seizure control and quality of life pacientes. Goal: Searching to increase understanding the role of the amygdala with intrinsic changes in neurotransmitter receptors and their subunits in ictogenesis mechanisms and epileptogenesis, enabling the improvement of surgical techniques currently used, as well as new therapeutic modalities, this study analyzed gene expression on the subunits of excitatory receptors, NMDA (NR2 and NR3A, GRIN2C and GRIN3A genes) and kainate (GluK1 and GluK2, GRIK1 and GRIK2 genes), and inhibitory receptor subunit GABA (?4 and ?5, genes GABRA4 and GABRA5 ), neuropeptide Y receptor subtypes (Y2 and Y5, and NPY5R with NPY2R gene) in the basolateral nucleus of human amygdala of patients with MTLE. Material and Methods: Amygdala fragments were used in 20 patients who made amigdalohipocampectomia with the Service neurosurgery HC-FMRP-USP, 10 patients with postoperative effective control (Engel 1) and 10 patients with inadequate control of seizures (Engel 3:04), and 10 amygdalas obtained from autopsies (control) using qPCR. Results: Were differences evidenced expression in NR2C subunits (p = 0.006) e?4 the GABAAr (p = 0.008), and subtype NPYr Y2 (p = 0.013), along with a tendency of NR3A subunits (p = 0.077). Showing no statistical significance in the analysis of GluK1 subunits (p = 0.147), GluK2 (p = 0.182) e?5 the GABAAr (p = 0.272), and the NPYr Y1 subtype (p = 0.242). Conclusion: The analyzes suggest differences in expression of neurotransmitter receptors in epilepsy patients on control containing the NR2C subunits and ?4 of GABAAr with NR3A subunits trends indicating amygdala neuronal modifications possibly involved in the epileptogenic zone, enabling therapeutic improvements with the refractory epilepsy treatment. As well can infer that the neural mechanisms involving the subunits ?4 GABAAr, GRIN2C and Y2 NPYr subtype in epileptogenesis and ictogenesis of TLE can be similar between the amygdala and hippocampus, while involving GLUK1 and GLUK2 subunits appear to be different; the GABRA5 gene can be used as endogenous control gene in studies of hippocampus and amygdala in TLE.

BACKGROUND: Finite element models of lung motion can aid in understanding mechanically driven lung deformation. Current finite element models consider each lung half as a continuum, lacking the ability to capture the displacement discontinuity at fissures caused by lobe sliding. OBJECTIVE: The objective of this work was to develop and evaluate finite element models for simulating lung motion that incorporate the role of sliding at the lobe boundaries. METHODS: Finite element models were developed from 4DCT of tidal breathing from five cancer subjects. To allow sliding, the lobes were modeled as independent bodies within a pleural cavity shell. Pleural cavity deformation was obtained from deformable image registration of the lung segmentations. Contact between the pleural cavity and lobes prevented penetration and allowed sliding at all interfaces. Lung parenchyma was modeled as a homogeneous, 2-parameter, Neo-Hookean finite elastic model. The parameters of the Neo-Hookean model, C1 and D1, were optimized by perturbation within realistic reported ranges; defined by the equivalent infinitesimal elasticity parameters: Young's modulus (from 0.7 kPa to 70 kPa) and ν (from 0.2 to 0.49). The frictional coefficient at fissures was perturbed between 0 (free sliding) and 1.5 (no sliding). 1,960 finite element analyses were performed across the five subjects. The optimal parameter ranges were evaluated by average landmark error and percentage of converged solutions. The developed finite element method, using optimized material and friction parameters, was further evaluated in a data set of six healthy subjects with image pairs spanning functional residual capacity (FRC) to total lung capacity (TLC). The finite element predicted displacement field for lobe sliding finite element models and continuum-based finite element models were compared using average landmark error and correlation with the lobe-by-lobe deformable image registration results. RESULTS AND DISCUSSION: The optimal parameters for Young's modulus were 49 kPa to 70 kPa and Poisson's ratio were 0.2 to 0.4. Variation of inter-lobar frictional coefficients did change displacement field accuracy assessed by landmark error or correlation to lobe-by-lobe deformable image registration. Characteristics of sliding predicted by the lobe sliding finite element models were consistent with characteristics in sliding observed in deformable image registration results. Also, variations in regional ventilation, quantified at the lobe level, were predicted by the finite element models and were shown to be influenced by the amount of lobe sliding allowed by the models.

Defining language lateralisation is important to minimise morbidity in patients treated surgically for temporal lobe epilepsy (TLE). Functional magnetic resonance imaging (fMRI) offers a promising, non-invasive, alternative strategy to the Wada test. Here, fMRI has been used to study healthy controls and patients with TLE in order (i) to define language-related activation patterns and their reproducibility; (ii) to compare lateralisation determined by fMRI with that from the Wada test; and (iii) to explore the usefulness of multiple fMRI language paradigms. 18 healthy controls (12 right-handed and 6 left-handed) and 24 pre-operative TLE patients (19 right-handed: 12 left-TLE, 7 right-TLE; 5 left-handed: 2 right-TLE, 3 left-TLE) were studied using fMRI. Four fMRI language paradigms used: phonetic and semantic fluency, and the naming of living and non-living things. The data for all 4 tasks were acquired during a single scanning session on two occasions. All patients also underwent Wada testing. In patients and controls, phonetic and semantic fluency tasks were robustly activating and strongly lateralising. Quantified language-related lateralisation from fMRI verbal fluency data was highly reproducible and concordant with the lateralisation of the Wada test. Both fluency tasks identified patients with atypical language lateralisation, including 4/12 right-handed patients with left-TLE and 4/5 left-handed TLE patients, regardless of the side of epileptic focus. In comparison, the two confrontational naming tasks were not strongly lateralising and did not reliably agree with Wada lateralisation in either 12 right-handed controls or 19 right-handed patients with TLE. However, there was a difference in the pattern of fMRI activation in right-handed pat ients with left-TLE. Left-TLE patients had a more right lateralised network of activation when naming living things relative to non-living things, suggesting that some patients may be at risk of a category specific naming decline for non-living things after left anterior temporal lobectomy. These results demonstrate that non-invasive fMRI measures of languagerelated lateralisation may provide a practical and reliable alternative to invasive testing for pre-surgical language lateralisation in patients with TLE. The high proportion of TLE patients showing atypical language lateralisation suggests considerable plasticity of language representation in the brains of patients with intractable TLE.