The Several Trials Extraction Of The Sptrague-Dawley Rats' Flash Visual Evoked Potentials And The Preliminary Research About The Action Potentials

Visual system is the most effective and reliable way for animals receiving outside information. After several billion years of long-term natural evolution, the animals' visual system has been proved to be one of the best information processing mechanism in the sensory system. Visual evoked potentials (VEPs) and the action potentials (spike) are very important and meaningful to study the visual system function and the visual information encoding mechanism in the primary visual cortex.Under the background, the FVEP and the action potentials were obtained through the Sptrague-Dawley rats' experiments, an algorithm of the several trials extraction of FVEP is proposed, and some preliminary study about the action potentials was completed in this paper. The following is the main study of this paper.(1) Acquisition of the experimental data. Based on the transmission mechanism of animal visual information, the primary visual cortex was chosen as the best site to record the experiment data. The FVEP and action potentials were recorded after designing the experiment and improvement of the experimental level.(2) The several trials extraction of FVEP. In order to extract the rats' visual evoked potentials recorded by implanted the electrodes in rats' primary visual cortex through several times, a method based on the independent component analysis (ICA) of a virtual channel and wavelet transform (WT) was proposed. Firstly, the noise and the FVEP were separated by ICA of the virtual channel. Then, the initial FVEP was extracted by averaging the separated FVEP several times. Finally, the left noise caused by inconformity of virtual channel and the real noise was decreased by wavelet transform. The effectiveness of the extraction method is demonstrated via the experiments of Sptrague-Dawley rats' FVEP and statistic analysis.(3) Some preliminary research about the action potentials. After analysing the fire frequency, inter spike interval(ISI), the fire spike rhythm and peri-stimulus time histogramme, some simple conclusions were obtained, such as the range of the fire frequency, and the random fire of spike.