Does "Glimcher's Neuroeconomics" specify exactly which hyperbolic function fits these monkey neurons? All the neural firing models I've seen are based on the sigmoid function, which at least is similar to some hyperbolics.

Also, just to point out, there isn't necessarily any association whatsoever between some complex human behaviour (such as discounting), and the firing dynamics of individual neurons.

Making that leap is similar to believing that the voltage activation functions of transistors in your latest intel processor is related to that function you keep seeing in your matlab program.