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Not different from @ChrisStronks answer. Just in different words. Just for everyone's knowledge — you are referring to the Voltage-clamp experiment. Situation 1: Sodium is depleted in the ECF. Despite the fact that Na+ conductance is much less than that of K+ and the equilibrium membrane potential (hyperpolarized) is closer to Nernst potential of K+, ...


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High sodium extracellularly means an increased sodium concentration gradient across the membrane. This means there is a larger driving force for sodium to enter the cell once the sodium channels open at the start of the action potential, and hence a larger depolarization takes place increasing the action potential amplitude. The enhanced depolarization leads ...


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Since the action potential question has already been answered, I will attempt to answer I'm sure this differs based on genetics and all sorts of other factors, but what are the general power ratings for the central nervous system? How much Watts/Volts/Amps travel with these signals? Are there standard ranges? You are right in that there is a large ...


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I don't want to comment about the nature of electric signals in neurons (as I know only little about physiology and neurophysiology). But here is a short answer that may already help you. Neuronal electric signals are called action potential. If you register the voltage at a given location on the axon of a neuron through time you will see something like ...


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Very nice question! I'll go through your three questions sequentially. Q1: Why does lower capacitance increase "the effectiveness of nearby nodes" or allow the depolarizing voltage to "travel not by ion diffusion, but as an electric field"? A: Capacitance basically results in sequestering of charge of opposite polarities along the cell membrane, which ...


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Excellent question! The difference is the fact that the rheobase is an example of a threshold measure. The threshold, as you correctly suggest, is the minimal energy (typically current level and not voltage as you suggest) to excite neural tissue. The threshold applies only under the specific experimental parameter settings used. These parameters include the ...


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The Hodgkin-Huxley model: $$I=C_m\frac{dV}{dt} + g_k(V_m - V_k) + g_{Na}(V_m - V_{Na}) + g_l(V_m- V_l)$$ Where $C_m$ is membrane capacitance per unit area and $g_i$ are membrane conductances. Reducing the number of channels does not affect capacitance per se (it does in a way) but what it basically does is to reduce membrane conductance to leak channels ...



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