It is almost inconceivable that a biological function would be dedicated to the past rather than the future of an organism. The only use for knowledge of the past is to prepare for a ‘good’ future by: learning from past experience, using the past to predict the future, judging choices by past outcomes, imagining possibilities and so on. A lot of research has gone into looking at how well memory records the past. Only a little research seems to ignore that and look at how well memory provides for a successful future. A recent review by D. Schacter (see Citation) looks at the research into the future aspect of memory.
The article points to some older research showing that the same core regions of the default network are used for memory of the past and imagining of the future and people with some types of amnesia also have difficulty imagining novel situations. But the body of the article deals with newer research.
Specifically, we have organized the literature with respect to four key points that have emerged from research reported during the past five years: (1) it is important to distinguish between temporal and nontemporal factors when conceptualizing processes involved in remembering the past and imagining the future; (2) despite impressive similarities between remembering the past and imagining the future, theoretically important differences have also emerged; (3) the component processes that comprise the default network supporting memory-based simulations are beginning to be identified; and (4) this network can couple flexibly with other networks to support complex goal-directed simulations. We will conclude by considering briefly several other emerging points that will be important to expand on in future research.
There is a very interesting distinction made about time. We have past, present and future; we can imagine various time relationships such as imagining some time in the future from the prospective of looking back at it from even further into the future. But we can also abandon identifying a particular time when we imagine. For example we can simulate what it would be like to be in another’s shoes or what it would be like to be in a different place. Instead of time-traveling, we can space-travel or identity-travel. It seem that the evidence so far implies that future and atemporal imagined events are represented similarly. But there are differences between temporal and atemporal imaginings. I find this distinction very interesting and something I had not really thought about before.
Another interesting idea (which I have thought about) is discussed with evidence for it.
The constructive episodic simulation hypothesis states that a critical function of a constructive memory system is to make information available in a flexible manner for simulation of future events. Specifically, the hypothesis holds that past and future events draw on similar information and rely on similar underlying processes, and that the episodic memory system supports the construction of future events by extracting and recombining stored information into a simulation of a novel event. While this adaptive function allows past information to be used flexibly when simulating alternative future scenarios, the flexibility of memory may also result in vulnerability to imagination-induced memory errors, where imaginary events are confused with actual events. a process of scene construction is critically involved in both memory and imagination. Scene construction entails retrieving and integrating perceptual, semantic, and contextual information into a coherent spatial context. Scene construction is held to be more complex than simple visual imagery for individual objects because it relies on binding together disparate types of information into a coherent whole.
There is much more of interest in this review. If you are interested in memory or simulations or the default network read the original paper.
Here is the abstract:
During the past few years, there has been a dramatic increase in research examining the role of memory in imagination and future thinking. This work has revealed striking similarities between remembering the past and imagining or simulating the future, including the finding that a common brain network underlies both memory and imagination. Here, we discuss a number of key points that have emerged during recent years, focusing in particular on the importance of distinguishing between temporal and non-temporal factors in analyses of memory and imagination, the nature of differences between remembering the past and imagining the future, the identification of component processes that comprise the default network supporting memory-based simulations, and the finding that this network can couple flexibly with other networks to support complex goal-directed simulations. This growing area of research has broadened our conception of memory by highlighting the many ways in which memory supports adaptive functioning.
Schacter, D., Addis, D., Hassabis, D., Martin, V., Spreng, R., & Szpunar, K. (2012). The Future of Memory: Remembering, Imagining, and the Brain Neuron, 76 (4), 677-694 DOI: 10.1016/j.neuron.2012.11.001