CHILD DEVELOPMENT PERSPECTIVES
The Emergence of Episodic Foresight and Its Consequences Thomas Suddendorf University of Queensland
ABSTRACT—Imagining
future events and adjusting current behavior accordingly is a hallmark of human cognition. The development of such episodic foresight is attracting increasing research attention. In this article, I review a selection of recent work on the emergence of episodic foresight and its role in different domains, including learning, deliberate practice, affective forecasting, intertemporal choices, and anxiety. Studies suggest that during the preschool years, children begin to consider future scenarios, enabling them to plan, prepare, and shape their future, but many other consequences, such as the role of developing foresight in anticipating hazards, remain unexamined. The potential predictive effects of early individual differences in episodic foresight on later cognitive capacities and developmental outcomes deserve closer scrutiny.
KEYWORDS—foresight; planning; mental time travel; prospection; development; deliberate practice
Over the last 10 years, researchers have shifted from an interdisciplinary preoccupation with studying cognitive processes that track the past to widespread interest in future-oriented cognition. It has become clear that people spend more time imagining the future than recollecting the past, and even when they recall, they often do so with a view toward what can be learned for the
Thomas Suddendorf, School of Psychology, University of Queensland. I thank the children who participated and the Australian Research Council for funding many of the studies described in this article. I also thank Jon Redshaw and three anonymous reviewers for helpful feedback on an early draft. Correspondence concerning this article should be addressed to Thomas Suddendorf, School of Psychology, University of Queensland, St Lucia, Qld 4072, Australia; e-mail:
[email protected]. © 2017 The Author Child Development Perspectives © 2017 The Society for Research in Child Development DOI: 10.1111/cdep.12233
future (1). In this article, I review progress in our understanding of the development of the ability to imagine future scenarios and organize action accordingly. Different terminology has been used to describe this capacity, including mental time travel into the future (2), episodic future thinking (3), episodic foresight (4), episodic prospection (5), and future-oriented mental time travel (6). To match the brevity of the term episodic memory, a special issue of Cognitive Development on this topic suggested using the term episodic foresight (7), which I do here. There are a variety of ways in which people can be driven by thoughts about the future, including semantic prospection about general regularities and prospective memory for intentions to perform actions in the future, but the foundational ability is the capacity to imagine future episodes (8). When we imagine future scenarios, we can consider the consequences of current events as well as particularities of situations completely removed from the here and now. This allows us to flexibly prepare and weigh options to take advantage of opportunities, manage threats before they manifest, and shape the future to our design. In short, episodic foresight is tremendously powerful and can be regarded as a quintessential human adaptive strategy (6, 9). In the following sections, I discuss the nature and assessment of the development of episodic foresight. Then, I explore recent work on consequences of its emergence. In spite of its remarkable power, this capacity also comes with a price, so I end with a brief discussion of the darker aspect of our ability to foresee future events. THE NATURE AND DEVELOPMENT OF EPISODIC FORESIGHT
How Do We Do It? A fundamental problem regarding the future is that it is uncertain. Although episodic foresight may have connotations of certainty, we are frequently wrong about what will happen. After all, we are not fortune-tellers or soothsayers. Much of our foresight is based on simple extrapolations from the past, for instance, when we predict that a past event will reoccur after a
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particular cue or period of time. In fact, considerable evidence (including from developmental research; 10, 11) suggests that episodic foresight is linked closely in mind and brain to episodic memory (8, 12, 13). Indeed, both may be regarded as two sides of the same coin, even if the future has priority in terms of evolutionary fitness (2). However, given that the future often differs from the past, episodic foresight involves more than an ability to predict reoccurrences. To simulate situations we have never experienced, we need an open-ended system that can combine and recombine old information into novel constellations—a flexible system that allows us to evaluate different possibilities (e.g., in terms of their value and likelihood of becoming reality). In addition to declarative memories, other component capacities are required to construct useful future scenarios, reflect on options, and embed them into larger narratives. Michael Corballis and I suggested a theater metaphor to highlight the diversity of sophisticated components involved (8). Like a real show, constructing mental scenarios involves a stage where the scene is entertained offline, a playwright to construct the narrative, actors that simulate acting in particular ways, and sets that represent objects and physical forces. Furthermore, something akin to a director is needed to evaluate and manage the scenarios, as well as an executive producer to decide what plan to put into action and a broadcaster to communicate mental scenarios with others. As this metaphor should make clear, episodic foresight is not an encapsulated module, but a faculty that draws on complex cognitive processes (e.g., working memory, recursive embedding, theory of mind, spatial reasoning, metarepresentation, executive functions, and language) that work together. We used the metaphor to evaluate the potential capacities of other animal species given that shortcomings in any one of these domains can limit foresight. However, it also highlights what young children need for effective episodic foresight to work (14). Assessing Children’s Capacities The simplest way to assess children’s capacity to think about future situations is to ask them directly (15). Results of studies using interviews suggest that while 2- and 3-year-olds can report some information about upcoming events, by ages 4 and 5, children can talk more clearly about future situations (11, 15). However, taking verbal reports at face value poses problems because children may understand more than they can articulate, and conversely, they sometimes say things they do not fully understand. Thus, the data should be supplemented with studies that focus on future-oriented behavior. Given that actions can be beneficial in the future only incidentally or because of associative learning and inherent predispositions, Corballis and I proposed strict behavioral criteria to rule out such alternative explanations for the apparently futuredirected behavior of young children (and animals). We advocated using single trials to avoid repeated exposure to the same stimulus–responses relationships, using novel problems to avoid
relevant learning histories, using different temporal/spatial contexts for the critical future-directed action to avoid cuing, and using problems from different domains to avoid specific behavioral predispositions (16). In studies aimed at meeting these criteria, 4-year-olds behaviorally demonstrated such flexible foresight (17). We introduced children to a novel problem in one room (a box with a certain tool that yielded a reward or a doll that needed a specific food) before taking them to another room. After spending 15 min on unrelated tasks, children were allowed to take one object back to the first room. Although 3-year-olds selected at chance, 4-year-olds tended to pick the options that allowed them to solve the problem in the other room. They used memory of a specific past episode from a spatially removed context and prepared for a return to these problems when presented with the opportunity. This finding has been replicated in studies in which selecting the object was separated by several minutes from returning to the room with the problem (18). By age 4, children can remember a novel problem well enough to recognize and secure its future solution when the chance presents itself. Although this and similar evidence (19) indicate that by the end of the preschool years, children have developed some fundamental prospective capacities, this does not mean that development stops at this stage or that younger children lack foresight altogether. For instance, even 3-year-olds begin to qualify statements about the future with verbal markers of uncertainty (e.g., maybe; 20). In a recent study, Jon Redshaw and I examined a simple but fundamental insight about future uncertainty: that it can be prudent to consider more than one possibility and prepare accordingly (21). We designed a minimalist paradigm through which children could demonstrate such insight. We dropped a desirable target into an upside-down Y-shaped tube and gave children the opportunity to catch it. Two-year-olds typically prepared for the drop by placing a hand under only one of the potential exits, and thus ended up failing on half the trials. Older children were more likely to prepare for both possibilities, with most 4-year-olds spontaneously covering both exits to the tubes from the first trial onwards without subsequently regressing to the less optimal response. The development of several component processes may drive this change in response. For instance, with the emergence of metarepresentational skills around this age (22), children may be able to reflect on the imagined possibility of the target coming out of one opening and conclude that this representation may be incorrect, driving them to prepare not only for this but also for the other possibility. More research is needed to determine what is supporting the prudent preparation. However, we now know that by this age, children can consistently prepare for at least two mutually exclusive versions of an immediate future event (21). (Chimpanzees and orangutans in this study performed similarly to the 2-year-olds.) Adults use episodic foresight to prepare for many more diverse, uncertain, and distant potential situations. We can imagine needs
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Episodic Foresight
we may experience and hazards we may encounter (e.g., on a planned holiday), which allows us to prepare for eventualities, to maximize future pleasure and minimize future discomfort. In contrast, young children struggle to consider their future needs (23) and prepare solutions for future problems (24), and this is not merely a function of poor memory for what is needed (25). Although by the end of the preschool years, children can prepare for some future needs, their capacities continue to develop throughout childhood and adolescence (5). For instance, in a recent study on narratives and introspections of 5-, 7-, and 9-yearolds, the development of foresight was more protracted than the development of episodic memory and required additional skills, though both capacities improved during middle childhood (26). A review of the developmental trajectories of the purported component capacities (see the theater metaphor mentioned earlier) suggests that although several milestones are reached around age 4, other critical aspects mature relatively late (14). For instance, children’s working memory capacity, the virtual stage on which future scenarios are entertained and evaluated, increases only gradually between ages 4 and 11 (27). More detailed charting of the development during middle childhood and beyond is desirable, given how fundamental episodic foresight is to human cognition. In the rest of this article, I consider consequences of this emerging capacity. CONSEQUENCES OF EPISODIC FORESIGHT
Shaping One’s Future Self People make different choices about what information to learn and what skills to acquire, and this largely accounts for the diversity in human expertise (28). We can set out to shape our future selves because we can think ahead and consider our future beings as continuous with our current selves as well as potentially different. Once we realize that we can influence that difference, we can change our future selves intentionally. A powerful way to do that is practice. Deliberate practice refers to our capacity to engage in repeated actions with the intention to improve our future skills (29). Research on deliberate practice has traditionally focused on the acquisition of outstanding adult levels of performance in sports and arts (30). However, deliberate practice is critical to the development of many ordinary skills, from learning how to write to learning a dance. In spite of the obvious importance of this capacity, little is known about how children begin to understand and use deliberate practice. Recently, we have begun to chart this development. In one study, my colleagues and I gave preschoolers the opportunity to selectively practice a motor task that would later earn them a reward if done well (31). Four- and 5-year-olds chose to engage with the relevant task at above-chance levels; 3-year-olds did not. In a second experiment, 5-year-olds, but not younger children, demonstrated explicit understanding of some of the effect of practice. Children were told a story about a competition of skills between two characters, one who tried the relevant skill just once
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and another who engaged in the activity every day for a long time. The older children predicted that the individual who tried repeatedly was more likely to win, and most of them stated practice as the reason. Furthermore, most 5-year-olds and a few 4-year-olds referred to practice or repetition when asked how they could improve a skill. Children who recognized that practice could help them improve were more likely to pick the character who had practiced in the previous task, and were more likely to practice a motor task to enhance their own future performance. In a recent follow-up study, my colleagues and I replicated these findings with a larger sample and examined competence in older children. Children’s capacity in this area increased with age: By age 7, many understood deliberate practice explicitly and practiced for the future without being prompted. We can identify similar developments in the context of acquiring knowledge. Young preschoolers have little understanding of how knowledge is formed (32). But by around age 5, they can distinguish someone who acquired knowledge yesterday from someone who will acquire it tomorrow, and they can identify whom to ask to acquire that information themselves (33). Studies similar to those on deliberate practice described earlier could chart children’s developing ability to seek out future-relevant information deliberately. Through aimed acquisition of knowledge and skills, we can shape the capacities of our future selves and, to a certain extent, become masters of our own destiny. The complex relationships between episodic foresight and education deserve closer research attention (5). Concern for One’s Future Feelings Episodic foresight allows us to foresee the affective consequences of future events. We care about how the future might make us feel. In research in social psychology that has examined this so-called affective forecasting, people typically overestimate the intensity of their future emotional reactions to events (34). For instance, people’s anticipated emotional distress over ending a relationship tends to be more extreme than what they report feeling once the relationship actually ends (35). Recently, we examined young children’s affective forecasting to determine if they start off making such biased predictions (36). In two experiments, children were told they were going to play games and asked to predict on a 7-point scale of happy to sad faces how they would feel if they were to win or lose. After finishing the games, the children were asked to rate how they felt. In both experiments, preschoolers demonstrated a negative intensity bias just as adults do. They anticipated that they would feel sadder after losing a game than they reported feeling after they lost the game. However, they did not show any sign of a positive intensity bias (i.e., they did not anticipate feeling happier than they were after winning). As this was the first study of this type, the result should be interpreted cautiously. We need to examine the emergence of affective forecasting more systematically, especially given continuing debate about the nature of the phenomenon (37).
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Intensity bias may have an important function, motivating people to avoid negative outcomes to events and strive for positive ones (38). After all, steps to secure future happiness often have to compete with more immediate motives, so exaggerating affective consequences may help increase future orientation. The development of inhibition of current temptation in view of anticipated greater payoffs in the future has been studied extensively with Mischel’s marshmallow test (39). Children gradually improve their ability to resist taking an immediate reward to receive a larger anticipated reward later (40). Remarkably, individual differences in future-oriented control predict a range of advantages even decades later (41). Nonetheless, delaying is not always prudent, especially if the future reward is uncertain or the future in general is anticipated to be bleak (42). In one study, 4-year-olds adjusted their waiting time depending on whether the future reward was likely to materialize. When the experimenter was unreliable in another context, children waited a shorter time for a promised larger reward than when the experimenter was reliable (43). Even preschoolers can adjust their delaying and saving behaviors in light of changing risk contingencies (44). I suspect that the capacity to foresee and evaluate future situations and the likelihood of their hedonic consequences, rather than just the ability to inhibit per se, is particularly adaptive and predictive of future successes. However, this is an empirical question that needs to be addressed in longitudinal research. Anxiety and Other Troubles With increasing foresight, children are confronted not only with opportunities to control and shape the future through planning and preparation, but also with threats. The future can be frightening and trigger considerable anxiety. In addition to fear in response to immediate threats, humans can consider potential future dangers even in the absence of present triggers. This enables people to avoid or manage dangers well before a threat is imminent. However, this capacity to autocue anxiety can also cause distress (45). Persistent worry about remote threats, or about dangers one cannot control, is problematic. We know little about the relationship between children’s emerging foresight and anxiety. The role of foresight in clinical conditions (e.g., anxiety, depression, schizophrenia) is increasingly attracting research attention (46). Impaired foresight is likely associated with many other behaviors, such as risk perception and drug abuse (47). Researchers in developmental psychology may want to consider findings in these fields. CONCLUDING REMARKS
Episodic foresight is a fundamental human capacity that has only recently become the focus of intensive study. Researchers have begun to chart the development of this capacity in children and identify factors influencing its emergence. However, many
important aspects of its role, for instance, in clinical contexts and applied domains (e.g., preventing accidents), remain largely unexamined. The potential predictive effects of early individual differences in episodic foresight on later cognitive capacities and success in school deserve research attention. I anticipate that over the coming years, we will see considerably more fruitful research on the development of foresight and it consequences. REFERENCES 1. Baumeister, R. F., Vohs, K. D., & Oettingen, G. (2016). Pragmatic prospection: How and why people think about the future. Review of General Psychology, 20, 3–16. doi:10.1037/gpr0000060 2. Suddendorf, T., & Corballis, M. C. (1997). Mental time travel and the evolution of the human mind. Genetic, Social, and General Psychology Monographs, 123, 133–167. 3. Atance, C. M., & O’Neill, D. K. (2001). Episodic future thinking. Trends in Cognitive Sciences, 5, 533–539. doi:10.1016/S1364-6613 (00)01804-0 4. Suddendorf, T. (2010). Episodic memory versus episodic foresight: Similarities and differences. Wiley Interdisciplinary Reviews. Cognitive Science, 1, 99–107. doi:10.1002/wcs.23 5. Prabhakar, J., Coughlin, C., & Ghetti, S. (2016). The neurocognitive development of episodic prospection and its implications for academic achievement. Mind, Brain, and Education, 10, 196–206. doi:10.1111/mbe.12124 6. Michaelian, K., Klein, S. B., & Szpunar, K. (Eds.). (2016). Seeing the future: Theoretical perspectives on future-oriented mental time travel. New York, NY: Oxford University Press. 7. Suddendorf, T., & Moore, C. (2011). Introduction to the special issue: The development of episodic foresight. Cognitive Development, 26, 295–298. doi:10.1016/j.cogdev.2011.09.001 8. Suddendorf, T., & Corballis, M. C. (2007). The evolution of foresight: What is mental time travel, and is it unique to humans? Behavioral and Brain Sciences, 30, 345–351. doi:10.1017/ S0140525X07001975 9. Suddendorf, T. (2006). Foresight and evolution of the human mind. Science, 312, 1006. doi:10.1126/science.1129217 10. Payne, G., Taylor, R., Hayne, H., & Scarf, D. (2015). Mental time travel for self and other in three- and four-year-old children. Memory, 23, 675–682. doi:10.1080/09658211.2014.921310 11. Suddendorf, T. (2010). Linking yesterday and tomorrow: Preschoolers’ ability to report temporally displaced events. British Journal of Developmental Psychology, 28, 491–498. doi:10.1348/02615100 9X479169 12. Klein, S. B. (2013). The temporal orientation of memory: It’s time for a change of direction. Journal of Applied Research in Memory and Cognition, 2, 222–234. doi:10.1016/j.jarmac.2013.08.001 13. Addis, D. R., Wong, A. T., & Schacter, D. L. (2007). Remembering the past and imagining the future: Common and distinct neural substrates during event construction and elaboration. Neuropsychologia, 45, 1363–1377. doi:10.1016/j.neuropsychologia.2006.10.016 14. Suddendorf, T., & Redshaw, J. (2013). The development of mental scenario building and episodic foresight. Annals of the New York Academy of Sciences, 1296, 135–153. doi:10.1111/nyas.12189 15. Hudson, J. A. (2006). The development of future time concepts through mother-child conversation. Merrill-Palmer Quarterly, 52, 70–95. doi:10.1353/mpq.2006.0005
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