我們的大腦主要是由神經元（neuron）及神經膠細胞（glia cell）兩種細胞所構成。關於神經科學的研究已有百年的歷史，然而遺憾的是，在過去，科學家們將研究聚焦於神經元之上，而忽略了神經膠細胞在神經系統中的貢獻。近年來，有越來越多研究結果顯示，神經膠細胞在大腦中扮演著相當重要的角色。科學家發現，愛因斯坦的神經膠細胞在大腦中所佔的比例高於一般人，此外，更有研究指出，智商較高的動物，神經膠細胞在大腦中所佔的比例亦較高。這些研究結果顯示，神經膠細胞與智力的發展有著密不可分的關係。本論文主要探討，神經膠細胞的存在與否，對於整體神經網路的影響。本實驗分為三個部分：首先，利用免疫螢光染色（Immunocytochemistry）來觀察整體細胞生長趨勢及密度變化之情形。其次，則是利用多電極陣列系統（multi-electrode array system），觀察在不同天數下，樣本的發放率（firing rate）之變化及同步爆發行為之變化。最後，由於NMDA受體在記憶以及學習上扮演著相當重要的角色，因此我利用不同藥物活化NMDA受體，藉以觀察神經膠細胞的有無是否會對於整體神經網路的同步爆發行為產生不同的影響。實驗結果顯示，在具有神經膠細胞的神經網路中，神經元會有聚集成團的現象，發放率亦隨培養天數增加而增加，且更容易有同步爆發的現象產生。而NMDA受體被活化時，神經網路的發放率提升，同步爆發的形態亦有明顯變化。

The brain is mainly consisted of two types of cells: neurons and glia. Neuroscientists have focused on the neuron. However the contribution of the glia cell had been long ignored. Recently, several studies suggest that the glia plays many important roles in the nervous system. It had been found that the ratio of glia to neurons for the famous physicist Albert Einstein is higher than normal human. In addition, another research showed that the ratio of glia to neurons increases with species’ intelligence. This thesis focuses on the role of the glia cell in the neuronal network. First, we use the immunocytochemistry to observe the trend of the cell growth and the density change. Second, we use the multi-electrode array system to record the changes in the firing rate and the synchronous bursting with and without glia with different days in vitro (DIV). Last, we investigate the effect of the NMDA receptor on the neuronal network. In order to investigate the effect of glia on synchronous bursting in neuronal network, we used different drugs to activate the NMDA receptor. We find that in the presence of glia in the neuronal network, the neurons tend to aggregate in clusters. Furthermore, the firing rates increase with DIV, and with higher probability of the synchronous bursting. When the NMDA receptors are activated, the form of the synchronous bursting are different for culture with and without glia.

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