[From Bill Powers (2004.07.07.1614 MDT)]
Mary obtained Khoo's "Physiological control systems" (recommended by Marc
Abrams) at a bargain price. Most of it is pretty familiar, though Khoo's
models of respiratory systems look useful. His model of the "dynamics of
neuromuscular reflex motion" (p.92ff), however, are pretty limited. Only
one joint angle is treated, and he omits the reference signal for the
stretch reflex (the gamma efferent signal). The Little Man model had gone
considerably beyond this model 15 years ago. It's possible, of course, that
Khoo deliberately chose a simplified model because this is intended as a
text for teaching.
For those interested, I was aware of most of these approaches to control
theory long ago, when I decided to go a different way.
Best,
Bill P.