The Application of Nonlinear Dynamic Analysis on Repetitive Transcranial Magnetic Stimulation Improving the Learning and Memory of Alzheimer's Disease Rats

CUI Guixue; YAN Hailiang; ZHANG Hongxing; YU Yi

doi:10.19529/j.cnki.1672-6278.2017.04.09

Abstract：To study the effects of repetitive transcranial magnetic stimulation ( rTMS) on the learning and memory of Alzheimer 's disease(AD) rats, and to discuss the application of nonlinear dynamic analysis in electroencephalograph (EEG) signal processing of rats.(1)60 Sprague-Dawley(SD) rats were randomly divided into group (rTMS+AD), group AD and control group, 16 rats in each group, and the remaining ones were used as spare rats .(2) To establish the AD rat model whose bilateral hippocampal area were in-jected with A beta amyloid protein (Aβ1-42), and to evaluate the model using Morris water maze .(3) 10 Hz rTMS was conducted on the group (rTMS+AD), and pseudo stimulation was done on the group AD and normal group for 14 d consecutively.(4) Morris water maze was used to test the learning and memory ability of rats in each group , and scalp EEG was obtained by Cerebus 64 channel electrophysiological signal recording system for 7 d consecutively .(5) The energy spectrum and LZ complexity of EEG signal in each group were acquired by MATLAB , and using SPSS software for statistically analysing of EEG and water maze data .(1) The escape la-tency of group AD was longer than that of normal group , and the average distance of group AD from the platform was longer than that of normal group, and the difference was statistically significant (P<0.05);The escape latency of group (rTMS+AD) was shorter than that of the AD group , and the average distance of group ( rTMS+AD) from the platform was closer than that of the AD group , and the difference was statistically significant (P<0.05);(2) The energy ratio of low frequency (delta+theta) and high frequency (alpha+beta) of group AD was higher than that of normal group .There was no statistical difference between the partial channels .The energy ratio of low frequency and high frequency of group ( rTMS+AD) was lower than that of group AD in occipital lobe , left temporal lobe , right temporal lobe and frontal lobe .In left parietal lobe and right parietal lobe , that was the opposite .Only the difference of left tem-poral lobe was statistically significant (P<0.05).(3) The LZ complexity of group (rTMS+AD) was higher than that of the AD group, the LZ complexity of group AD was lower than that of normal group , and the difference was statistically significant (P<0.05). rTMS can improve the learning and memory ability of AD rats and increase the LZ complexity of its EEG signal .LZ complexity is more suitable for objectively diagnosing of AD and evaluating the effect of rTMS on EEG signal in AD rats than the power spectrum estimation based on AR model .