摘要
利用神经纤维的无源电缆模型描述神经纤维在磁刺激下的阈下行为,通过数字仿真得出了神经纤维在不同频率的磁刺激感应电场作用下阈下膜电位的时间特征包括波形和幅度,发现高频的感应电场诱导作用下得到的膜电位幅值小于低频电场的性质。同时采用积分变换频域分析的方法,得出了在不同空间分布的感应电场诱导刺激作用下神经纤维的响应特性,发现和低频比较,高频的空间分布函数频率成分的感应电场诱导得到的膜电位幅值较低。计算出在刺激线圈中采用典型刺激电流作用下在神经纤维响应得到的膜电位的特征。从时空两域阐述神经纤维对不同时变磁场诱导作用下的阈下响应行为,对磁刺激仪中刺激线圈的刺激电流的选择和线圈尺寸的设计都具有指导意义。
A pa ssive cable model for electromagnetic induction is employed to describe subthreshold behavior of a nerve fiber. By numeric simulation, subthr eshold membrane potential parameters including waveform and amplitude in a nerve fiber induced by electromagnetic field with different frequen cy are acquired. It is found that the membrane potential induced by high frequency electromagnetic field is less than that induced by low frequency. Integral transform is employed to acquire response character istic of nerve fiber induced by electromagnetic field with different s patial distribution. It is found that membrane potential induced by hi gh frequency components of the spatial distribution function is less t han that in-duced by low frequency components. Membrane potential induc ed by several typical current waveform in the stimulating coil are ca lculated. Subthreshold behaviors of nerve fiber induced by electromagnet ic field with different parameters are explained by time and space an alysis which provides theoretical foundation for the device of the coi l current and size of the coil for a magnetic stimulator.
出处
《生物物理学报》
CAS
CSCD
北大核心
2002年第3期331-335,共5页
Acta Biophysica Sinica
