Frequency response of evoked potential in normal and diseased nerve muscle

We examined the nerve-muscle response using principles of control theory. In vivo experiments allow control of other factors that may also influence muscle response. We propose that nerve-muscle response might consist of three transfer functions: nerve, end-plate, and muscle. In general, nerves can respond until about 1000 Hz stimulation, so the results of this experiment were not greatly influenced by the transfer functions of nerves. That is, the results of this study were influenced by the transfer function of end-plate and muscle. Ensuing research should, therefore, strive to identify individual peripheral nerve, end-plate, and muscle responses. Furthermore, in order to apply the results of this study to human muscle, the following matters need to be considered: (1) Our model does not take into account that the major part of human muscles are composed of different fiber types. (2) Muscle properties depend on age, metabolic and nutritional state, and on the level of muscular activity before the experiment. Our experiments demonstrated the controlling factors of nerve-muscle condition and have shown that the neuromuscular control system can be described by methods of control theory.