電位影像螢光光子統計之模擬研究

Abstract

本研究的重點在於從光子統計的角度出發，創造一個關於雙光子電位影像的模擬方法。由於目前在雙光子電位影像的領域當中，其影像礙於散粒雜訊的限制下，以至於電位影像的亮度成為一項至關重要的議題。本研究也曾致力於做小鼠中腦黑質致密部（ＳＮｃ）的電位影像研究，然而同樣受限於平均光子數不足，以至於無法看到明顯電位變化。因此，我們從光子統計的角度出發，設計了一套模擬方法，去研究電位影像中的電信號被偵測的可能性。 在本研究的模擬當中，假設了一套完美的量測系統，將重心放在光子數的統計行為上面。以此證明，假若在完美量測系統的條件下，模擬出無法偵測到螢光變化，那麼真實情況便更不可能足以達到可偵測電位訊號的條件。 本研究的模擬方法，提供了相關電位影像實驗的設計去做電位信號評估。依照本研究總結出的幾個重要相關參數，可以評估參數下的實驗條件，其電位信號被偵測的靈敏度及準確率。

The point of this study was to create a two-photon voltage imaging simulation from the perspective of photon statistics. In the field of two-photon voltage imaging, the quality of the images is often limited by shot noise, making brightness a critical issue for the detectability of voltage signals. Our research initially involved in vivo experiments using the ASAP4e GEVIs in the substantia nigra pars compacta (SNc) of the mice brain. However, the experiments were limited by low photon counts, which prevented the detection of clear voltage signals. Thus, from the perspective of photon statistics we designed a simulation method, to investigate the possibility of spike detection in voltage imaging. In the simulation of this study, a perfect measurement system was assumed, focusing on the photon statistical behavior. This is to demonstrate that if voltage signal spikes cannot be detected even under ideal conditions, their detection under real experimental conditions would be impossible. This thesis has provided a simulation method to relevant voltage imaging experiments, assessing the voltage signal quality. Based on some important parameters in the summary of this thesis, it is able to evaluate the spike detection sensitivity and precision under the experimental parameters.