[Animal modeling] - Establishment of rat fear stress model and analysis of its visual cognitive effect

  Objective: To construct rat models of different levels of fear stress and explore the effect of fear stress on visual cognitive ability of LE rats

  Methods: The foot shock was used as a stress stimulus to design a cognitive choice experiment. The neural response signals of the amygdala region were collected for functional network analysis to evaluate the visual cognitive effect of rats. First, the experimental rats were divided into strong (S+), weak (S) fear stress groups and control groups (N), and the foot shock stimuli of different intensities were set respectively; Then, the visual cognitive enhancement training of single figure "△" is carried out; Finally, a visual choice test experiment was conducted with double graphs ("△" and "ten" graphs). In addition, combined with the complex network theory, a visual cognitive function network of amygdala nuclei in fear stressed rats was constructed, and the information transmission efficiency of the brain functional network was characterized by the average path length and clustering coefficient

  Results: The time required to complete the visual cognitive intensive training was significantly higher in the S+group than in the S and N groups. The time required to complete the visual cognitive intensive training was significantly higher in the S+group than in the N group at the early stage of the intensive training, and there was no significant difference between the two groups at the late stage; In the cognitive choice experiment, both group S and group N formed a visual cognitive connection, while group S+did not form a visual cognitive connection; In the analysis of brain function network, effective visual information transmission was formed between neurons in amygdala of group S and group N, but not in group S+

  Conclusion: Fear stress has a negative impact on visual cognition, and the cognitive effect becomes significantly worse with the increase of fear