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Hi all,
I am trying to use the linear mechanism in order to model ephaptic interactions. According to the online reference, arguments of the linear mechanism are in units/cm2. For example, the conductance vector g has dimensions of S/cm2. In my case, this vector represents the transverse conductance of the extracellular space. How can I specify the area, in other words in which area the S/cm2 conductance refers to?

Thank you in advance,
Stamatis

It is the area of the compartment (segment) to which the node of the electrical device (resistor or capacitor) connects.

Only equations (matrix rows) that add to the current balance equations need units consistent with the current balance equations. Matrix rows not associated with segments can have any units you wish (though they should be self-consistent with respect to the chosen user meaning of c*y' + g*y = b)

It may help to look at "proc fill_eqn" in nrn/lib/hoc/lincir/lincir1.hoc to see how I multiply certain rows by -100/area(location)

So, the value of the transverse conductors will vary depending on the area of the respective segments. In my model of myelinated fiber, nodes for example have smaller areas than internodes, so the transverse conductors that correspond to nodes will have a smaller value than the ones that correspond to internodes. This may not be physiologically consistent. Is there a way that I can assign the same transverse conductance to all compartments, independently of their individual geometry?