  The spontaneous transitions between D-dimensional spatial maps in an
attractor neural network are studied. Two scenarios for the transition from on
map to another are found, depending on the level of noise: (1) through a mixed
state, partly localized in both maps around positions where the maps are most
similar; (2) through a weakly localized state in one of the two maps, followed
by a condensation in the arrival map. Our predictions are confirmed by
numerical simulations, and qualitatively compared to recent recordings of
hippocampal place cells during quick-environment-changing experiments in rats.
