# Current fluctuations with reduced capacity

I simulate a neuron by compartments, where each compartment is represented by an electrical circuit. Myelinated nerves have reduced capacitance - so for example, if $$n$$ denotes the membrane layers, then the capacitance is C/n measured in [uF/cm^2]. Shouldn't random current fluctuations become smaller when capacitance is reduced? However, they do become larger - i.e. the random SCh fluctuations for a capacitance of

$$C = 1 [uF/cm^2]$$ are smaller than for $$C = 1/5 [uF/cm^2]$$ for example.

But does that make sense?

I model a neuron with a multi compartment model of the Hodgkin Huxley type - this means that the membrane voltage of each compartment can be determined with the HH equations. this figure shows the soma and with two adjacent compartments. If I reduce the capacitance of the soma, then (measured at the end of the axon) the fluctuations in the membrane voltage increase instead of decreasing.

• Probably a better fit for physics.stackexchange.com or electronics.stackexchange.com I would also help if you add a schematic of your modelling circuit. What happens to any current depends on the entire circuit and not just on a single component – Hilmar Apr 24 at 12:12
• @Hilmar i have edited the question :) – CB95 Apr 24 at 13:47