The role of affect across decision contexts [electronic resource] : from neural mechanisms to market-level behavior
Keywords: Psychology.

How do people make decisions regarding the people and ideas they financially support? While there are many individuals and causes in need all around the world, why is it that some people and organizations receive donations while others do not? The existing literature leaves many questions regarding the affective and neural systems that underlie these choices unanswered. Additionally, questions remain regarding the scalability of conclusions derived from existing studies. In particular, do empirical laboratory findings accurately describe the way people behave in the real world when confronted with similar decisions? Further, do these findings represent economically significant effects in large real-world samples? The answers to these outstanding issues will help elucidate the mechanism that subserve charitable giving and funding, and hold the potential for informing decision-making in both public policy and industry In this set of studies I seek to understand the role of affect in a variety of decision contexts, and subsequent influences on preference and choice. Using an interdisciplinary set of tools, including behavioral experimentation, market-level data analysis, and neuroimaging, I explore two related lines of inquiry. First, I examine the influence of affective responses in a series of decision scenarios, which vary with respect to the balance between prosocial and individual motivations. In a second related line of investigation, I extend and apply what we learn through laboratory experiments to explore the potential for using neural and behavioral measures of affect to describe and predict market-level behavior in the real world. In study 1 we address unresolved questions about how affect influences charitable giving decisions by soliciting donations from human subjects during behavioral and neural (i.e., functional magnetic resonance imaging or FMRI) experiments. We sought to determine whether and how affect might promote the identifiable victim effect, or peoples' tendency to preferentially give to identified versus anonymous victims of misfortune. Behaviorally, subjects gave more to orphans depicted by photographs versus silhouettes, and their shift in preferences was mediated by photograph-induced feelings of positive arousal, but not negative arousal. Neurally, while photographs versus silhouettes elicited activity in widespread circuits associated with facial and affective processing, only nucleus accumbens (NAcc) activity predicted and could statistically account for increased donations. In study 2 we sought to extend this work on affect and giving to microlending. Based upon earlier work, we hypothesized that loan requests that elicited more positive affect would accrue higher levels of funding. Analyzing a large internet database of over 13,000 real microloan requests, we found that positive affective features of attached photographs promoted loan request success. In a subsequent neuroimaging study, we then established that neural activity associated with positive affect (i.e., in the nucleus accumbens) and self-reported positive arousal ratings in our laboratory cohort significantly predicted loan request success not only within the group but also on the internet -- above and beyond the laboratory group's actual choices. In study 3 we extend these findings to the burgeoning internet crowdfunding market, in which individual motives are less clear. The mix of self- and other-interested motives involved in project funding raises important questions about which factors eventually lead to funding. We asked individuals to make incentive compatible decisions regarding the funding of actual crowdfunding projects as they underwent scanning. While self-report measures predicted individuals' own decisions to fund, their group average was unrelated to the real-world funding success on the internet. However, activity in a brain region associated with positive affect and identified in our previous work (i.e., the nucleus accumbens) successfully predicted these real-world outcomes. These findings suggest that in some scenarios, affective components of choice may forecast aggregate behavior better than choice itself. The three papers presented here use a combination of behavioral experimentation, market-data analysis, and neuroimaging methodologies to explore the role of affect in decisions that involve various levels of prosocial motivation. These findings indicate that affective and neural mechanisms are integral to financial decisions spanning charitable giving, microlending, and crowdfunding. Further, neural data may be able to predict market-level behavior in the real world beyond what is possible using traditional behavioral methods. Together, this dissertation highlights affective neuroscience's potential to probe neuropsychological mechanisms of choice and forecast market-level behavior.