Electrophysiological Characteristics And Model Optimization In Rats In The Resting State And Anesthesia State

Resting-state and anesthesia Electroencephalography(EEG)is an electrophysiological technique which is used for clinically diagnose of cortical dysfunction and monitoring anesthesia status.Animal models play an important role in the study of pathology and pharmacology.Resting-state EEG,especially in eyes-closed and eyes-open conditions,can provide information for the diagnosis of cortical dysfunction.However,the resting-state EEG study of rat is still absent.In addition,for the anesthesia monitor methods,there is not a method that can match the behavior of pain with the brain response.Therefore,in the present article,the rat's resting-state and anesthesia state were explored with the electrophysiological technique and compared with human brain resting-state results.In the resting-state study,by recording the human's resting-state EEG and rat's resting-state electrocorticography(ECoG)during eyes-closed and eyes-open conditions,we found that the differences of spectral power between eyes-closed and eyes-open is similar between humans and rats,that is,the low frequency amplitudes are higher and the high frequency amplitudes are lower in the eyes-closed condition.However,the specific differences in frequency ranges and scalp topographic distribution are different between two species,that is,human EEG spectral amplitudes in the eyes-closed condition were significantly higher at 8-12 Hz and 18-22 Hz in the occipital region,and significantly lower at 18-22 Hz and 30-100 Hz in the frontal region.Rat ECoG spectral amplitudes were significantly higher in the eyes-closed condition than that in the eyes-open condition at 1-4 Hz,8-12 Hz,and 13-17 Hz in the frontal-central region.(2)the 1/f-like power spectrum scaling analyses showed that the a values of the linear fits were significantly higher in the eyes-closed condition than in the eyes-open condition at parietal-occipital and frontal regions for both species.In the anesthesia state study,by recording rat's spontaneous and evoked cerebral response(i.e.,the laser evoked potentials)from awake to anesthesia state,and comparing the results with results in human,we found that(1)during the anesthesia process,for human and rat,the changes of low frequency oscillations are similar both in the amplitudes and scalp distributions.(2)The time domain features of laser-evoked potentials can distinguish awake and anesthesia state,while time-frequency domain features can distinguish different anesthesia depths.In summary,the present article establishing animal models for the study of resting-state and anesthesia,revealing the similarities and differences between species in resting-state and anesthesia state,provided a neurological basis for future research on psychophysiology and anesthesia depth monitoring researches,and found some indicators which can be applied in cross-species researches and transformation studies.