Sunk Costs and Games: A Suggestion for Future Research From an Animal Crossing Fan.

Complex decision making, and even more notably, complex economic decision making is an integral part of daily life. As a result, understanding the underlying neurological basis of such decisions is essential both to our increased scientific understanding of the brain and to our ability to diagnose and treat patients with neuropathologies. Sweis et al. (2018) explored the phenomenon of "sunk costs" and regret in mice, rats, and humans, finding similar sensitivities in their decision-making across species. In foraging tasks, subjects spent time waiting for rewards-- but their time was limited. They found that all species, mice, rats, and humans, demonstrated sunk cost effects. More notably, with increased investment amounts came increased sunk cost effects. While previous assumptions suggested that non-human animals like mice and rats were not capable of such complex thinking, Sweis et al. have shown the contrary. This, along with their collaborators' work in other animal models and in neurodivergent human populations, opens up the possibility to study these phenomena in other places we may not have considered before. For example, Dr. Sweis mentioned in his talk that he is interested in studying the development of complex decision-making in young children for this reason. 

To bridge these ideas, Sutter et al. (2018) conducted a review of the development of economic behavior and decision-making in children with respect to differences in age, gender, socio-economics, and other factors. Specifically, they focused on the rationality of choices, risk preferences, time preferences, social preferences, cooperation, and competitiveness. In many of the experiments discussed by Sutter et al., games were used with children as an engaging task to measure behavior. In terms of potential avenues for future research, it is possible to expand the use of games in experimental neuroscience research for their benefits to the field. 

Though video games are not new, they are increasing in popularity and accessibility for children and adults alike. One game that lends itself well to discussions of research in economic decision making is Animal Crossing: New Horizons (ACNH). This game includes explicit economic elements like loans, mortgages, and trading as well as illustrating aspects of economics like supply and demand, goods and services, and features of the stock market. As a result, teachers use this popular game as an educational tool, but there are lots of opportunities to practice economic decision making in the game outside of educational contexts too. 

For example, in ACNH, turnips can be bought and sold for different prices throughout the week. Although some savvy fans of the game have created algorithms to best determine when to buy and sell, most of the time, players have to decide to take that day's offer or take their chances and try again another day. The turnips will rot after a week, so time is a finite resource, and "going back in time" (by manipulating the game console) for a missed opportunity will also cause the turnips to rot and render them useless. Similar to Sweis et al.'s foraging task, players in ACNH face sunk costs. The amount of time, bells (ACNH's in-game currency), holding space, and other resources the player invests in turnips will affect how they make decisions about the value of their turnips. When offers are made, these factors can be compared against the offer for players to decide when and if to sell their turnips for a profit (or loss). 

Though a commercial game, ACNH and other video games provide lots of benefits that could be harnessed by neuroscientists, particularly researchers like Dr. Sweiss who study the type of decision-making that is present in ACNH as a core game element. ACNH is typically played on a daily basis and in addition to being saved to a console, can be uploaded to the internet for use by researchers. Additionally, ACNH is marketed for children age 7 and up but is also played by younger kids and is frequently played by adults due to the legacy of the franchise. This provides the opportunity to study the development of economic decision making over a large period of time with a large range of age groups. 

While a game like ACNH may not be ideally suited for the controlled type of research often found in experimental settings, it can be used as a powerful model for future game design in science if not itself harnessed for research. In their evaluation of current developmental research in economic decision making, Sutter et al. commented that "little is known about what happens to one type of economic behavior when another type of economic behavior is targeted in a specific intervention. While it is highly welcome to understand how interventions shape economic behavior in one particular domain, one important avenue for future research will be to examine potentially unintended side-effects." In this way, the complexity of ACNH gameplay where players are making multiple types of economic decisions at once and in tandem with each other may provide a more ecologically valid and valuable look at how these decisions are made. There is so much data that can be mined from the saved data of participants that are already playing this game, so much so that it would be advisable to consider its potential for this area of research. If not just for advancing our scientific understanding of the development of complex decision making, this type of research could also provide interdisciplinary insights into the use of games in education as a form of learning, the science behind our increasing relationship with games in a digital world, and how games can be harnessed in serious scientific research to study anything from the neurological basis of "fun" to the rehabilitation opportunities of virtual reality for Parkinsons patients. 

References: 

Sweis, B. M., Abram, S. V., Schmidt, B. J., Seeland, K. D., MacDonald, A. W., Thomas, M. J., & Redish, A. D. (2018). Sensitivity to "sunk costs" in mice, rats, and humans. https://science.sciencemag.org/content/361/6398/178.full.

Sutter, M., Zoller, C., Glätzle-Rützler, D. (2018). Economic behavior of children and adolescents–a first survey of experimental economics results. https://doi.org/10.1016/j.euroecorev.2018.09.004.