  Additive noise is known to produce counter-intuitive behaviors in nonlinear
dynamical systems. Previously, it was shown that systems with a deterministic
limit cycle can display bistable switching between metastable states in the
presence of asymmetric additive white noise. Here, we systematically analyze
the dynamics of this bistable behavior and show how the vector field away from
the limit cycle influences the rate and directionality of the bistable
switching. Using stochastic phase reduction methods, we identify mechanisms
underlying different rates of switching and predict when the system will rotate
in the opposite direction of the deterministic limit cycle. Thus, this work
presents an alternative mechanism for generating a range of bistable
switch-like behaviors that have been observed in a number of physical systems.
