【作者】 王放；

【导师】 孙心德；

【作者基本信息】 华东师范大学 ， 生理学， 2006， 硕士

【摘要】 应用常规电生理学技术，以神经元的特征频率（Characteristic frequency，CF）和频率调谐曲线（Frequency tuning curve，FTC）为指标，研究大鼠听皮层神经元特征频率（Characteristic frequency）的可塑性。 一．大鼠听皮层神经元频率感受野可塑性的模式 在给予的条件刺激频率（Conditioned stimulus frequency，CSF）和神经元特征频率（Characteristic frequency，CF）相差1.0kHz范围内，条件刺激可诱导50％以上神经元特征频率（Characteristic frequency）发生完全偏移，并可分为向频率调谐曲线（FTC）的低频端偏移、高频端偏移，或两侧均可偏移三种类型。其中，神经元的特征频率（Characteristic frequency）高、Q₁₀-dB值大和频率调谐曲线对称指数（Symmetry index）大于零的神经元，其特征频率（Characteristic frequency）偏向频率调谐曲线（FTC）高频端的概率更高。结果提示，经验可改变大鼠听皮层神经元的特征频率（Characteristic frequency）。 二．不同的条件刺激参数和背景噪音对听皮层神经元特征频率（Characteristic frequency）可塑性的影响 1．在给予的条件刺激频率（Conditioned stimulus frequency，CSF）和神经元的特征频率（Characteristic frequency，CF）相差±1.0kHz范围内，不同声音强度的纯音刺激对神经元的特征频率（Characteristic frequency）可塑性有不同的诱导结果。当纯音刺激强度（Sound level or Intensity）为最低阈值（Minimum threshold，MT）以上+5dB的条件下，只有少数神经元（9.09％）的特征频率（Characteristic frequency）能发生转移。条件刺激的声音强度（Sound level or Intensity）为神经元最低阈值以上+20dB时，神经元的特征更多还原

【Abstract】 Using conventional electrophysiological technique, we investigated the plasticity of characteristic frequency (CF) of neurons in rat auditory cortex (AC) by determining CF and frequency tuning curve (FTC) shifts of neurons.1. In the AC, when the frequency difference between conditioned stimulus frequency (CSF) and the CF of neuron was in 1.0 kHz with conditioned stimulation for 30 min, 61 of 120 neurons (50.8%) completely shifted their CF to the CSF. According to the CF shift direction, complete CF shifts were classified into three patterns: CF shifts toward lower frequency side (LFS) of neuron’s FTC. CF shifts to higher frequency side (HFS) and CF shifts to both LFS and HFS. Among them, some neurons with higher CF, bigger Q10-dB value and symmetry index >0, the probability of CF shift toward HFS of FTC is higher than other neurons. The results suggest that the experience can alter CF in rat auditory cortical neurons.2. Parameters of conditioned stimulus and CS paired with noise differ the plasticity of neuron in primary cortex of rat(1) Intensity/Sound level of conditioned stimulus differs the type of CF plasticity. When the intensity/sound level was +5dB above minimum threshold and the CF of neuron was in 1.0 kHz with conditioned stimulation for 30 min, only 9. 09% neurons shift non-completely and the rest have no shift. When the intensity/sound level is +20dB above the更多还原