Banca de DEFESA: TANDARA OLIVEIRA BENEVIDES SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : TANDARA OLIVEIRA BENEVIDES SILVA
DATA : 01/03/2021
HORA: 17:00
LOCAL: INSTITUTO DE CIÊNCIAS DA SAÚDE
TÍTULO:

Characterization of the dynamics of Functional Networks of Brain Synchrony in Epilepsy.

PALAVRAS-CHAVES:

Epilepsy. Functional Brain Networks. Temporal Connectivity. Acoustic nonperiodical stimulation. Complete Synchronization Time. EEG.

PÁGINAS: 67
GRANDE ÁREA: Ciências Biológicas
ÁREA: Biologia Geral
RESUMO:

epilepsy is characterized by changes in excitability and neuronal synchrony that lead to disorders in the brain network. Currently, about a third of patients have pharmacoresistance, so, neurostimulation has been used as an adjunctive treatment. In this context, the temporal structure of the stimulus has been shown to be essential for therapeutic efficacy. The electrical non-periodical stimulation (NPS), has shown significant anticonvulsant effects providing a basis for the development of studies in humans. The use of Acoustic nonperiodical stimulation (ANPS) following the NPS showed beneficial clinical results in patients with refractory epilepsy. Objectives: to evaluate the ANPS effects in functional cerebral synchrony networks in refractory epilepsy, from a dynamic perspective; to assess whether there were changes in dynamic functional connectivity after using ANPS treatment; to assess whether there was an increase in the Complete Synchronization Time (CST) after treatment. Methodology: from the electroencephalographic (EEG) records of patients with refractory epilepsy, in the interictal state, functional brain networks (RFC) were generated, represented by time-varying graphs (TVG) and aggregate static networks (ASN). We used the motifs synchronization association method and evaluated dynamic indices such as the degree of temporal connectivity and the CST. The effect of the ANPS was assessed for the acute phase (n = 11 patients) and up to the fifth day of stimulation (n = 8 patients). Results: the temporal connectivity decreased and increased significantly, on the first and fifth days, respectively. The distribution of edge weights showed a reduction (acute effect) and an increase on the fifth day, for the most frequent edges, with the maintenance of the highest weight edges, in all states. CST showed trends opposite to those of connectivity. While the most representative hubs showed variation in location, with no changes in connectivity or amount of synchronization. Discussion: Our results point to an acute effect of the EANP of a general reduction in the dynamic connectivity of the network, followed by an apparent habituation of the connectivity and amount of synchronization. In addition to a maintenance of the most important connections in the network, and a continuous change of the electrode’s hubs, in the network indicating a probable reorganization of the network. Conclusion: our results showed that the ANPS has a modulating effect on brain synchrony and that the temporal structure of the stimulus constituted a major factor for this, new assessments are necessary to verify the variability of topological connection patterns over time.

MEMBROS DA BANCA:
Presidente - 988860 - EDUARDO PONDE DE SENA
Externo(a) ao Programa - 1994820 - RAPHAEL SILVA DO ROSARIO
Externo(a) à Instituição - WELLINGTON PINHEIRO DOS SANTOS - UFPE