Similarities between remembering past events and

imagining future events had also been documented in a study of depressed patients (Williams DAPT et al., 1996) as well as in behavioral studies of healthy individuals (e.g., D’Argembeau and Van der Linden, 2004, 2006; Spreng and Levine, 2006; Suddendorf and Busby, 2005), and were explored in experiments that investigated whether non-human animals can project into the past or future (e.g., Clayton and Dickinson, 1998; Emery and Clayton, 2001). Social psychologists had published studies concerning the role of mental simulations in predicting future experiences and the role of memory in guiding such simulations (e.g., Morewedge et al., 2005). Moreover, several review papers had discussed relevant theoretical and conceptual issues (Atance and O’Neill, 2001, 2005; Clayton et al., 2003; Ingvar, 1979, 1985; Suddendorf and Corballis, 1997; Tulving, 1985, 2002a, 2002b, 2005; Wheeler et al., 1997). Building on these foundational studies and analyses, the papers published in 2007 served to galvanize scientific interest in the relations between remembering the past and imagining the future, as evidenced by the rapidly growing number of papers on the topic that

have been published since. The main purpose of the present article is to review some of the progress that has been made since 2007 (our review will focus exclusively on studies with human subjects, but relevant recent work has also been conducted with nonhuman animals; for reviews, see Cheke and Clayton, 2010; Crystal, 2012; Roberts, XAV-939 concentration 2012; van der Meer et al., 2012). 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 to 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. Note that although the focus of our review will be to elucidate recent advances in understanding the neural mechanisms of memory-based simulations, numerous purely behavioral studies have also shed light on the topic and we will consider those data where appropriate. Throughout the review, we will use the concepts of imagination or “imagining the future” and simulation or “simulating the future” in a roughly interchangeable manner. Schacter et al. (2008; p.