大鼠皮层脑电和海马电位的复杂度和功率谱分析

A Study of Complexity and Power Spectrum of Cortical EEG and Hippocampal Potential in Rats under Different Behavioral States.

目的分析大鼠皮层脑电和海马电位在觉醒和睡眠各期的复杂度和功率谱特性 ,以及两种电信号的复杂度值与功率谱分布之间的关系。方法通过慢性埋植电极采集自由活动大鼠皮层脑电和海马电位 ,计算其算法复杂度Kc值、近似熵ApEn值 ,以及功率谱和功率谱重心频率。 结果海马电位在任何时期的复杂度值都显著高于皮层电位 ;皮层电位的复杂度值在非快动眼 (NREM )睡眠期最小 ,海马电位的复杂度值在清醒期最大 ,两电位的总功率在NREM睡眠期最大。结论两种复杂度值Kc和ApEn与脑电功率谱的频率分布具有密切关系 ,功率谱中具有明显的高峰时 ,信号复杂度降低。复杂度指标可以区分大鼠皮层和海马电位之间的差别 。

Objective To study the complexity and the power spectrum of cortical EEG and hippocampal potential in rats under waking and sleep states. Method Cortical EEG and hippocampal potential were collected by implanted electrodes in freely moving rats. Algorithmic complexity (Kc), approximate entropy (ApEn), power spectral density (PSD) and gravity frequency of PSD of the potential waves were calculated. Result The complexity of hippocampal potential was higher than that of cortical EEG under every state. The complexity of cortical EEG was lowest under the state of non rapid eye movement(NREM) sleep. The complexity of hippocampal potential was highest under waking state. The total power of both potentials in 0.5～30 Hz frequency band showed their highest values under NREM state. Conclusion The values of Kc and ApEn are closely related to the distributions of PSD. When there are evident peaks in PSD, the complexities of signals will decrease. The complexities may be used to distinguish the difference between cortical EEG and hippocampal potential, or large differences between the same kind of potentials under different behavioral states