Additional efficient computation of branched nerve equations: adaptive time step and ideal voltage clamp
Related Experiment Video
Updated: Oct 16, 2026

Dynamic Clamp Methods to Investigate Impaired Neuronal Excitability Associated with Autism
Published on: October 17, 2025
1Unité de Neurosciences Integratives et Computationelles, Institut Alfred Fessard--CNRS, Gif-sur-Yvette, France. lyle@cogni.iaf.cnrs-gif.fr
Abstract:
Various improvements are described for the simulation of biophysically and anatomically detailed compartmental models of single neurons and networks of neurons. These include adaptive time-step integration and a reordering of the circuit matrix to allow ideal voltage clamp of arbitrary nodes. We demonstrate how the adaptive time-step method can give equivalent accuracy as a fixed time-step method for typical current clamp simulation protocols, with about a 2.5 reduction in runtime. The ideal voltage clamp method is shown to be more stable than the nonideal case, in particular when used with the adaptive time-step method. Simulation results are presented using the Surf-Hippo Neuron Simulation System, a public domain object-oriented simulator written in Lisp.
Related Concept Videos
Node Analysis for AC Circuits
To unravel the complexities of this system, nodal analysis is employed, a powerful technique founded on Kirchhoff's current law (KCL), which remains valid for phasors. AC circuits can effectively be...
Calculations of Electric Potential II
Consider a...
Nodal Analysis with Voltage Sources
Consider a circuit that contains four resistors and two voltage sources, as shown in Figure 1. One of these voltage sources is connected between a...
Nodal Analysis
Consider, for instance, a simple circuit composed of three nodes and three resistors, as shown in...
Calculations of Electric Potential I
The ring is divided into infinitesimal small arcs such that point M is equidistant from all the arcs. Here, the cylindrical coordinate system is used to calculate the electric potential at point M. A general element of the arc between angles θ and θ + dθ is of the length Rdθ and has a charge of λRdθ.
The Role of Ion Channels in Neuronal Computation
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.

