Search results
Results from the WOW.Com Content Network
In neuroscience, rheobase is the minimal current amplitude of infinite duration that results in the depolarization threshold of the cell membranes being reached, such as an action potential or the contraction of a muscle. [1]
Currents produced by the opening of voltage-gated channels in the course of an action potential are typically significantly larger than the initial stimulating current. Thus, the amplitude, duration, and shape of the action potential are determined largely by the properties of the excitable membrane and not the amplitude or duration of the ...
The current clamp technique records the membrane potential by injecting current into a cell through the recording electrode. Unlike in the voltage clamp mode, where the membrane potential is held at a level determined by the experimenter, in "current clamp" mode the membrane potential is free to vary, and the amplifier records whatever voltage ...
Mathematically, the membrane voltage can be modeled by a conductance-based model with an input given by the applied current () and an output given by the membrane voltage (). Hodgkin and Huxley's original conductance-based model, which represents a neuronal membrane containing sodium and potassium ion currents , as well as a leak current , is ...
Rate of ionic flow through the channel, i.e. single-channel current amplitude, is determined by the maximum channel conductance and electrochemical driving force for that ion, which is the difference between the instantaneous value of the membrane potential and the value of the reversal potential. [20]
where I is the total membrane current per unit area, C m is the membrane capacitance per unit area, g K and g Na are the potassium and sodium conductances per unit area, respectively, V K and V Na are the potassium and sodium reversal potentials, respectively, and g l and V l are the leak conductance per unit area and leak reversal potential ...
Electrical input–output membrane voltage models – These models produce a prediction for membrane output voltage as a function of electrical stimulation given as current or voltage input. The various models in this category differ in the exact functional relationship between the input current and the output voltage and in the level of detail.
The membrane time constant measures the amount of time for an electrotonic potential to passively fall to 1/e or 37% of its maximum. A typical value for neurons can be from 1 to 20 ms. The membrane length constant measures how far it takes for an electrotonic potential to fall to 1/e or 37% of its amplitude at the place where it began.