Highly Efficient Propagation of Random Impulse Trains Across Unmyelinated Axonal Branch Points: Modifications by Periaxonal K+ Accumulation and Sodium Channel Kinetics

This chapter addresses the divergence of axonal information at branch points, specifically comparing the extent to which impulse-based information incident to a branch point differs from that which is emitted from that branch point.

In the study described here, the propagation of random trains of impulses across single or serially arranged symmetrical branch points in unmyelinated axons was simulated. Single-impulse propagation illustrated the axial modifications of the point-to-point conduction velocity (hereafter: "CV( x )") through primary and secondary serial branch points. Poisson-like random stimulation elicited wide-band impulse trains to assess possible frequency-modulated distortion during impulse propagation within the arborization. Possible modifications due to periaxonal K+ accumulation or the kinetic description of Na+ conductance were also considered.