In addition to creating chains of events surrounding the seed situation, theta oscillation mechanisms may help link events that are separated at longer timescales. For example, during navigation in the rat, the interleaving assemblies representing the current location are occasionally replaced by an entirely different assembly in a single theta cycle74, as if the rat ‘mentally jumped’ transiently to another location. Such jumps from one representation to another are frequent when the identity of the environment is made ambiguous by training rats in two visually distinct environments and ‘teleporting’ them from the one to another by changing the light patterns. In this case as well, the cell assembly contents, representing either one or the other environment, can switch back and forth in a few or even single theta cycles88. Extended, ‘look-ahead’ sequences representing large distances, from the start to the goal, can also occur, especially at critical junctures of choice behavior in memory tasks89,90. Place cells also often intermingle with internally generated ‘retrospective’ and ‘prospective’ neurons45,58,59.
