The Response Characteristics And Tolerance Of Pigeon's Ectostriatum Neurons To The Visual Learned Targets

The learned target mainly refers to that the organism learns the target which organisms obtained by experience in life,and grasps the knowledge of target under specific conditions.Birds have extremely developed visual systems and powerful learning abilities,and ectostriatum is a senior nucleus in the tectofugal pathway of the bird visual system,which is involved in visual information processing of bird learned target.However,it's still unclear that the response characteristics of pigeon's neurons in ectostriatum to the visual learned target and their tolerance to the change of the learned target.The study of response characteristics and tolerance analysis of pigeons' ectostriatum neurons to visual learned targetis of great significance for analyzing the cognitive mechanism of pigeon's visual system and constructing a new brain-like model.In this study,pigeons,as animal models,were trained to perform cognitive tasks on specific targets,and the electrical activity of ectostriatum neurons was recorded simultaneously.From the perspective of different response features of spike and local field potential,the response characteristics of pigeon's ectostriatum neurons to visual learned targets and their tolerance to various target transformations were quantitatively analyzed.The main work and results of this study are summarized as follows,(1)A cognitive behavior training program was designed to train pigeons on learned target.The results showed that the training accuracy of pigeons could reach more than0.9 after 6 to 7 days.Pigeons can still recognize the target which is changed,and the training accuracy can reach more than 0.85 quickly and stably.(2)Combined with signal collection technology and histological method,the depth orientation of the implanted microelectrode array was determined,and the data of the ectostriatum neurons were collected synchronously during the behavior training of pigeons.The pretreatment operation of spike and local field potential signals of the effective neurons was completed.(3)The response features of neurons in ectostriatum were extracted and analyzed in terms of the correlation coefficient between the signals of neurons in different trials,the cluster sparsity before and after learned target,and the mutual information between two neurons.The results showed that most information of the response features,including spike firing rate and power of LFP,were mainly concentrated in the target presentation period before learned target.the response of neurons in ectostriatum shifted from the target presentation stage to decision stage after learned targets.Compared with the stage of before learned target,the correlation coefficient between neuron signals in different trials is higher,and the redundant information between neuron clusters is reduced.And the synchronicity and reliability of response features of neurons in ectostriatum of pigeons were enhanced,neurons clusters can use fewer spikes to transfer and encode the information of visual cognition,which is embodied the dynamic and efficiency of the neural information processing mechanism.(4)The tolerance of the above neurons response features to target transformations(including position,size or occlusion)was analyzed.The results show that the main information of neurons response features after target transformation of position or size shrink to half,is still concentrated in the decision-making stage.And there is high correlation between corresponding signals before and after any of these target transformations,indicating that the features of spike firing rate and the LFP energy in the gamma sub-band are not sensitive to change after any of these target transformations.In addition,after target transformations of size shrink twice or disturb is increased,the main information of the two signal features of neurons is adjusted from concentrated on the decision-making stage to the target presentation stage.And the signal correlation of neurons before and after any of these target transformations is not high,indicating that the two features are more sensitive to change after any of these target transformations.