| 论文简介 |
Nonlinear response of neuron firing under external electromagnetic radiation as well as trans-
membrane current, as two kinds of external forces, are studied in an improved Fitzhugh-Nagumo
(FHN) model. The control effects of external forces to neuron firing are measured by winding
number Ω during mode transition of motion types. The phenomenon of match and mismatch
between the angular frequency ωoutand the angular frequency of external forcing can be ex-
plained by whether the winding number is 1/1 or not. Ω remains several constants like 1/1, 1/2
and 1/3 etc. When increasing amplitude of transmembrane current I0, so that it distributes in
a stair-like structure in parameter space before the system enters chaotic state when I0is large
enough. The scenarios of motion type switching are different between and beyond in the stairs.
Besides, the occurrence and the disappearance of chaos are accompanied with a riddling of the
orbit with variation of parameters which temporarily spoils the toroidal topology and induces
chaotic oscillation. Indeed, nonlinear response to external forces is pivotal to neuron firing and
its control. |
(创新港)
