Now, researchers from Washington University in St. Louis have used advanced brain imaging techniques to show that remembering the past and envisioning the future may go hand-in-hand, with each process sparking strikingly similar patterns of activity within precisely the same broad network of brain regions.

Results of this study offer a tentative answer to a longstanding question regarding the evolutionary usefulness of memory,” McDermott concludes. “It may just be that the reason we can recollect our past in vivid detail is that this set of processes is important for being able to envision ourselves in future scenarios. This ability to envision the future has clear and compelling adaptive significance.