基于鸽局部场电位信号的数字字符图像重建研究

Digital Character Image Reconstruction on the Basis of Local Field Potential Signals of Pigeons

利用鸽视顶盖神经元对视觉图像刺激产生的局部场电位信号(LFP),重建刺激数字字符图像。采用微电极阵列记录数字图像扫屏刺激下的神经元LFP信号,对其进行傅里叶变换并提取幅值、相位特征,然后利用逆滤波器算法构造重建模型,重建数字图像,并采用互相关系数进行评价。研究结果发现,在最优通道组合下,依据单因素重建试验,确定重建模型下神经元对视觉刺激的响应延迟时间为0.01 s,响应持续时间为0.55 s,频带范围为1 Hz<f1<30 Hz、140 Hz<f2<240 Hz。在各单因素最优的条件下,通过重建模型重建4只鸽子8组数据的10幅数字字符图像(0~9),与原始图像相比,其互相关系数均超过了0.90,总体互相关系数为0.935±0.01。总之,数字图像的扫屏视觉刺激模式所诱发的神经元响应可以以信息积累的方式重建该视觉刺激图像,同时也表明LFP信号的幅值、相位特征可较好地表征视觉刺激图像。

The digital character image was reconstructed by the pigeon optic tectum neurons using local field potential signal(LFP)generated by visual image stimulation.The microelectrode array was used to record the LFP signal of the neuron under the stimulus of the digital image scanning screen.The Fourier transform was performed to extract the amplitude and phase characteristics.Then the reconstruction model was constructed by using the inverse filter algorithm,and the digital image was reconstructed.The cross-correlation coefficient was used to evaluate the reconstruct digital image.This study found out that with the optimal channel combination,according to the single-factor reconstruction test,the response delay time of neurons to visual stimuli under the reconstructed model was 0.01 s,the response duration was 0.55 s,and the frequency band range was 1 Hz<f1<30 Hz、140 Hz<f2<240 Hz.Under the optimal conditions of each single factor,the cross-correlation coefficient of the ten-digital characters images(0~9)reconstructed from 8 sets of data of 4 pigeons by reconstruction model exceed 0.90 compared with the original image,and the overall cross-correlation coefficient was 0.935±0.013.In short,the neuron response induced by the scanning visual stimulation pattern of digital images can reconstruct the visual stimulation image by means of information accumulation.It also showed that the amplitude and phase characteristics of the LFP signal represented the visual stimulation image better.