313 research outputs found
História da Filosofia III
Livro didático dedicado a História da Filosofia Moderna produzido para o curso EaD Licenciatura em Filosofia da UFSC. Capítulo 1: Descartes e a Autoridade da Razão; Capítulo 2:Kant e a Filosofia Transcendental; Capítulo 3:Kant leitor de Berkeley; Capítulo 4: Hume: para além do Empirismo
Memorial de Atividades Acadêmicas
Memorial sobre a trajetória acadêmica.Memorial de atividades acadêmicas apresentado para a progressão para a Classe de Professor Titular do Departamento de Filosofia da UFSC e
Focusing narrowly or broadly attention when judging categorical and coordinate spatial relations: A MEG study
We measured activity in the dorsal system of the human cortex with magnetoencephalography (MEG) during a matching-to-sample plus cueing paradigm, where participants judged the occurrence of changes in either categorical or coordinate spatial relations (e.g., exchanges of left versus right positions or changes in the relative distances) between images of pairs of animals. The attention window was primed in each trial to be either small or large by using cues that immediately preceded the matching image. In this manner, we could assess the modulatory effects of the scope of attention on the activity of the dorsal system of the human cortex during spatial relations processing. The MEG measurements revealed that large spatial cues yielded greater activations and longer peak latencies in the right inferior parietal lobe for coordinate trials, whereas small cues yielded greater activations and longer peak latencies in the left inferior parietal lobe for categorical trials. The activity in the superior parietal lobe, middle frontal gyrus, and visual cortex, was also modulated by the size of the spatial cues and by the type of spatial relation change. The present results support the theory that the lateralization of each kind of spatial processing hinges on differences in the sizes of regions of space attended to by the two hemispheres. In addition, the present findings are inconsistent with the idea of a right-hemispheric dominance for all kinds of challenging spatial tasks, since response times and accuracy rates showed that the categorical spatial relation task was more difficult than the coordinate task and the cortical activations were overall greater in the left hemisphere than in the right hemisphere
High-Throughput Method of Whole-Brain Sectioning, Using the Tape-Transfer Technique
Cryostat sectioning is a popular but labor-intensive method for preparing histological brain sections. We have developed a modification of the commercially available CryoJane tape collection method that significantly improves the ease of collection and the final quality of the tissue sections. The key modification involves an array of UVLEDs to achieve uniform polymerization of the glass slide and robust adhesion between the section and slide. This report presents system components and detailed procedural steps, and provides examples of end results; that is, 20mum mouse brain sections that have been successfully processed for routine Nissl, myelin staining, DAB histochemistry, and fluorescence. The method is also suitable for larger brains, such as rat and monkey
Brainstem evoked potentials and magnetic resonance imaging abnormalities in differential diagnosis of intracranial hypotension
Objective: To compare brainstem acoustic evoked potentials (BAEP)and magnetic resonance imaging (MRI)in the differential diagnosis of intracranial hypotension (IH), Chiari malformation (CM)and sensorineural hearing loss (SNHL). Methods: BAEP were recorded in 18 IH, 18 CM, 20 SNHL patients and 52 controls. MRI were acquired in all IH and CM patients. Results: Abnormal BAEP were observed in 94% of IH patients, in 33% of CM and 70% of SNHL patients. After recovery from IH, BAEP abnormalities disappeared. Internal auditory canal (IAC)MRI abnormalities were described in 88% of IH patients. MRI signs of IH were observed in 33\u201378% in IH patients, but the most frequent MRI sign was 8th nerve T2 hyperintensity, with contrast enhancement in T1 sequences. This finding, combined with wave I latency, yielded highest specificity and sensitivity for IH diagnosis. Conclusions: Our study points out how IH can be effectively distinguished from CM and SNHL through the contribution of neurophysiology and MRI; in particular, evaluation of the 8th nerve achieves a high sensitivity and specificity in patients with IH. Further studies are required to examine the combined use of BAEP recordings ad MRI in diagnosis and monitoring of patients affected by IH
Fundamentos Filosóficos da Educação
Livro didático de Fundamentos Filosóficos da Educação, preparado pelos professores do Departamento de Filosofia da UFSC Marco Franciotti, Delamar Dutra, Darlei Dall´Agnol, utilizado no Curso de Licenciatura em Matemática na Modalidade à Distância.Ua
Cortical Network Topology in Prodromal and Mild Dementia Due to Alzheimer\u2019s Disease: Graph Theory Applied to Resting State EEG
Graph theory analysis on resting state electroencephalographic rhythms disclosed topological properties of cerebral network. In Alzheimer\u2019s disease (AD) patients, this approach showed mixed results. Granger causality matrices were used as input to the graph theory allowing to estimate the strength and the direction of information transfer between electrode pairs. The number of edges (degree), the number of inward edges (in-degree), of outgoing edges (out-degree) were statistically compared among healthy controls, patients with mild cognitive impairment due to AD (AD-MCI) and AD patients with mild dementia (ADD) to evaluate if degree abnormality could involve low and/or high degree vertices, the so called hubs, in both prodromal and over dementia stage. Clustering coefficient and local efficiency were evaluated as measures of network segregation, path length and global efficiency as measures of integration, the assortativity coefficient as a measure of resilience. Degree, in-degree and out-degree values were lower in AD-MCI and ADD than the control group for non-hubs and hubs vertices. The number of edges was preserved for frontal electrodes, where patients\u2019 groups showed an additional hub in F3. Clustering coefficient was lower in ADD compared with AD-MCI in the right occipital electrode, and it was positively correlated with mini mental state examination. Local and global efficiency values were lower in patients\u2019 than control groups. Our results show that the topology of the network is altered in AD patients also in its prodromal stage, begins with the reduction of the number of edges and the loss of the local and global efficiency
Complexity Analysis of Spontaneous Brain Activity in Attention-Deficit/Hyperactivity Disorder: Diagnostic Implications
Background: Attention-deficit/hyperactivity disorder (ADHD) is defined as the most common neurobehavioral disorder of childhood, but an objective diagnostic test is not available yet to date. Neurophychological, neuroimaging, and neurophysiological research offer ample evidence of brain and behavioral dysfunctions in ADHD, but these findings have not been useful as a diagnostic test. Methods: Whole-head magnetoencephalographic recordings were obtained from 14 diagnosed ADHD patients and 14 healthy children during resting conditions. Lempel-Ziv complexity (LZC) values were obtained for each channel and child and averaged in five sensor groups: anterior, central, left lateral, right lateral, and posterior. Results: Lempel-Ziv complexity scores were significantly higher in control subjects, with the maximum value in anterior region. Combining age and anterior complexity values allowed the correct classification of ADHD patients and control subjects with a 93% sensitivity and 79% specificity. Control subjects showed an age-related monotonic increase of LZC scores in all sensor groups, while children with ADHD exhibited a nonsignificant tendency toward decreased LZC scores. The age-related divergence resulted in a 100% specificity in children older than 9 years. Conclusions: Results support the role of a frontal hypoactivity in the diagnosis of ADHD. Moreover, the age-related divergence of complexity scores between ADHD patients and control subjects might reflect distinctive developmental trajectories. This interpretation of our results is in agreement with recent investigations reporting a delay of cortical maturation in the prefrontal corte
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