  We propose to compute the effective activation energy, usually referred to a
pseudopotential or quasipotential, of a birhythmic system -- a van der Pol like
oscillator -- in the presence of correlated noise. It is demonstrated, with
analytical techniques and numerical simulations, that the correlated noise can
be taken into account and one can retrieve the low noise rate of the escapes.
We thus conclude that a pseudopotential, or an effective activation energy, is
a realistic description for the stability of birhythmic attractors also in the
presence of correlated noise.
