4 resultados para Functional areas

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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Abstract Background Catching an object is a complex movement that involves not only programming but also effective motor coordination. Such behavior is related to the activation and recruitment of cortical regions that participates in the sensorimotor integration process. This study aimed to elucidate the cortical mechanisms involved in anticipatory actions when performing a task of catching an object in free fall. Methods Quantitative electroencephalography (qEEG) was recorded using a 20-channel EEG system in 20 healthy right-handed participants performed the catching ball task. We used the EEG coherence analysis to investigate subdivisions of alpha (8-12 Hz) and beta (12-30 Hz) bands, which are related to cognitive processing and sensory-motor integration. Results Notwithstanding, we found the main effects for the factor block; for alpha-1, coherence decreased from the first to sixth block, and the opposite effect occurred for alpha-2 and beta-2, with coherence increasing along the blocks. Conclusion It was concluded that to perform successfully our task, which involved anticipatory processes (i.e. feedback mechanisms), subjects exhibited a great involvement of sensory-motor and associative areas, possibly due to organization of information to process visuospatial parameters and further catch the falling object.

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Background: In the presence of turbinate dysfunction, an inferior turbinectomy for persistent hypertrophy of bone and/or mucosa may be performed. We sought to explore anatomic feasibility of a transoral turbinectomy. Methods: After transoral inferior turbinectomy in 12 cadavers, average distances from the external nasal valve to inferior turbinate and from pyriform aperture to inferior turbinate were compared. Average "area of access" was calculated. Preoperative and postoperative nasal length, tip projection, and alar-base width were also compared. Results: Average distance from external nasal valve to inferior turbinate was 32.4 mm. Average distance from aperture to inferior turbinate was 2.4 mm (P < 0.0001). Average "areas of access" to nasal vault through the external nasal valve and mouth were 183.9 mm(2) and 243.6 mm(2) (P = 0.07), respectively. Conclusions: The transoral approach provides a larger "area of access" to the turbinate, a statistically significant reduction of distance to target, no postoperative changes in nasal soft tissue, and easier instrumentation.

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Abstract Background Recently, it was realized that the functional connectivity networks estimated from actual brain-imaging technologies (MEG, fMRI and EEG) can be analyzed by means of the graph theory, that is a mathematical representation of a network, which is essentially reduced to nodes and connections between them. Methods We used high-resolution EEG technology to enhance the poor spatial information of the EEG activity on the scalp and it gives a measure of the electrical activity on the cortical surface. Afterwards, we used the Directed Transfer Function (DTF) that is a multivariate spectral measure for the estimation of the directional influences between any given pair of channels in a multivariate dataset. Finally, a graph theoretical approach was used to model the brain networks as graphs. These methods were used to analyze the structure of cortical connectivity during the attempt to move a paralyzed limb in a group (N=5) of spinal cord injured patients and during the movement execution in a group (N=5) of healthy subjects. Results Analysis performed on the cortical networks estimated from the group of normal and SCI patients revealed that both groups present few nodes with a high out-degree value (i.e. outgoing links). This property is valid in the networks estimated for all the frequency bands investigated. In particular, cingulate motor areas (CMAs) ROIs act as ‘‘hubs’’ for the outflow of information in both groups, SCI and healthy. Results also suggest that spinal cord injuries affect the functional architecture of the cortical network sub-serving the volition of motor acts mainly in its local feature property. In particular, a higher local efficiency El can be observed in the SCI patients for three frequency bands, theta (3-6 Hz), alpha (7-12 Hz) and beta (13-29 Hz). By taking into account all the possible pathways between different ROI couples, we were able to separate clearly the network properties of the SCI group from the CTRL group. In particular, we report a sort of compensatory mechanism in the SCI patients for the Theta (3-6 Hz) frequency band, indicating a higher level of “activation” Ω within the cortical network during the motor task. The activation index is directly related to diffusion, a type of dynamics that underlies several biological systems including possible spreading of neuronal activation across several cortical regions. Conclusions The present study aims at demonstrating the possible applications of graph theoretical approaches in the analyses of brain functional connectivity from EEG signals. In particular, the methodological aspects of the i) cortical activity from scalp EEG signals, ii) functional connectivity estimations iii) graph theoretical indexes are emphasized in the present paper to show their impact in a real application.

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Abstract Background Cerebral Palsy (CP) presents changes in posture and movement as a core characteristic, which requires multiprofessional clinical treatments during children’s habilitation or rehabilitation. Besides clinical treatment, it is fundamental that professionals use evaluation systems to quantify the difficulties presented to the individual and their families in their daily lives. We aimed to investigate the functional capacity of individuals with CP and the amount of assistance required by the caregiver in day-to-day activities. Methods Twenty patients with CP, six-year-old on average, were evaluated. The Pediatric Evaluation Inventory of Incapacities was used (PEDI - Pediatric Evaluation Disability Inventory), a system adapted for Brazil that evaluates child's dysfunction in three 3 dimensions: self-care, mobility and social function. To compare the three areas, repeated measures analysis of variance (ANOVA) were used. Results We found the following results regarding the functional capacity of children: self-care, 27.4%, ±17.5; mobility, 25.8%, ±33.3 and social function, 36.3%, ±27.7. The results of the demand of aid from the caregiver according to each dimension were: self-care, 9.7%, ±19.9; mobility, 14.1%, ± 20.9 and social function, 19.8%, ±26.1. Conclusion We indicated that there was no difference between the performance of the subjects in areas of self-care, mobility and social function considering the functional skills and assistance required by the caregiver.