  The mechanisms of information transmission are investigated in a lattice of
coupled continuous maps, by analyzing the propagation of both finite and
infinitesimal disturbances. Two distinct regimes are detected: in the former
case, both classes of perturbations spread with the same velocity; in the
latter case, finite perturbations propagate faster than infinitesimal ones. The
transition between the two phases is also investigated by determining the
scaling behaviour of the order parameter.
