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4.3 Results on Branched Cells
The RSW model is in its early stages of development, but the goal of this section
is not to demonstrate a complete solution. Rather, I offer evidence that this model
can yield higher accuracy than the POD and DEIM reduced model, and that the
RSW model may permit accurate simulation of larger, more highly branched cells
than are currently feasible.
I have tested the RSW model on two branched cells with two different weakly
excitable channel models. The familiar forked neuron from the previous sections
appears again as the most basic branched cell to test. In order to show the utility of
the model on larger cells, I use neuron pl8 from (Vetter et al., 2001), which is the
pyramidal cell shown in Figure 4.2. For both cells I use the MIG channel model of
Table B.3, but I also use a modified version of this model to demonstrate the effect
of having purely passive dendrites beyond a certain distance from the soma. This
model, called MIG-P, contains the exact same parameters as the MIG model except
that the conductances (except the leak conductance) are set to zero for compartments
whose distance to the soma is greater than 400 pm.
4.3.1 Forked Neuron Results
Consider again the forked neuron which has one parent branch and two child
branches, all with radius 1 pm and length 500 pm. The transition point xγ is located
20 pm from the distal end of the parent branch. Using a compartment length of