Structures in coupled map lattices

We report the observation of coherent structures in coupled map lattices. We define the coherent structures as those in which the values of the dynamical variables follow a certain pattern. Larger size coherent structures are observed as the coupling parameter increases. There is also an increase in the number of structures with a given size or lifetime. If noise is added to the system, then there is a considerable increase in the number as well as the size of coherent structures.