The name is absent

70

request. All computations were performed using MATLAB version 7.4 (R2007a) on a
Sun Ultra 20 computer with a 2.2 GHz AMD Opteron processor. Detailed simulation
documentation can be found in the Supplementary Material of (Kellems et al., 2010).

Three ion channel models were used in this study. One follows Hodgkin-Huxley
kinetics, while the second augments this model by including an A-type K⁺ current
with a spatially-varying conductance density given by

G_a(x) = 4.15(1 + τ∕100),                      (3.22)

where x is the distance (in μm) from the soma. We refer to these models as HH and
HHA, respectively. Parameters for these two models are the same as given in Tables
B.l and B.2. The third model seeks to mimic weakly excitable dendrites, following
the kinetics and spatially-varying conductance densities of (Migliore et al., 1999). We
refer to this model as MIG, and we give its parameters in Table B.3.

3.2.3.1 Computational Notes

Since the soma is large but assumed to be isopotential, its surface area is often
greater than that of any dendritic compartment. A common practice in coding the
solution to (3.2) is to divide each ODE by the surface area of the corresponding com-
partment. While this is mathematically sound, it yields entries in H (and potentially
other quantities) that can vary by orders of magnitude, resulting in poor accuracy
for the reduced system. The solution is to not divide through by surface area, which

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