Study on synchronous firing dynamics in rat cortical neuronal network

• Main Authors: WEI-YEN WOON, 溫偉源
• Other Authors: Lin-I
• Format: Others
• Language: en_US
• Online Access: http://ndltd.ncl.edu.tw/handle/36250377010451533846

博士 === 國立中央大學 === 物理研究所 === 93 === Abstract We study the synchronous firing activities in cortical neuronal network culture. Under depletion of extracellular Mg2+, synchronous firing activity is observed using confocal fluorescence microscopy. The firing patterns of the synchronous firing activities are found to closely correlated to the network morphology. It is found that the high density culture develops into synchronous firing prior to the low density one at early stage. The firing frequency of synchronous firing is generally an increasing function of day in vitro (DIV). It is further found that the high density culture develops into unique firing pattern with high rate bunched firing peaks separated by long quiescence periods. Using non-linear dynamics analysis, we analyze the phase diagram of the inter-event interval (IEI) of synchronous firing and reconstruct the strange attractor structure. It is found that the strange attractor exhibits period two characteristics and the histograms of IEI show double peak and broader distribution for the unique firing pattern. The mechanism behind the emergence of the long quiescence period is investigated by measuring the correlation between the long quiescence and long bursting period, and explained in term of extended ion depletion. Using fast line laser scanning, we identify master and slave during synchronous firing, showing spatiotemporal heterogeneity in the synchronous firing activity. Micro-dissection is performed to perturb the synchrony of the network firing activity as a preliminary est for the small world network architecture.