  We study the overdamped motion of a Brownian particle in a driven double-well
system to understand various physical phenomena observed experimentally. These
phenomena include hysteresis, stochastic resonance, and net unidirectional
motion in a symmetric periodic system. We argue that the area of the hysteresis
loop so defined is a good measure of synchronization (with respect to the
applied field) of passages between the two wells. We find that stochastic
resonance may be relevant even in case of large amplitude driving field due to
a recently discovered phenomena of noise induced stability of unstable states.
We try to find relation between some of these apparently different phenomena.
