Knowledge that Transforms

Scholars have been using hypothetical dilemmas to investigate moral decision making for decades. However, whether people’s responses to these dilemmas truly reflect the decisions they would make in real life is unclear. In the current study, participants had to make the real-life decision to administer an electroshock (that they did not know was bogus) to a single mouse or allow five other mice to receive the shock. Our results indicate that responses to hypothetical dilemmas are not predictive of real-life dilemma behavior, but they are predictive of affective and cognitive aspects of the real-life decision. Furthermore, participants were twice as likely to refrain from shocking the single mouse when confronted with a hypothetical versus the real version of the dilemma. We argue that hypothetical-dilemma research, while valuable for understanding moral cognition, has little predictive value for actual behavior and that future studies should investigate actual moral behavior along with the hypothetical scenarios dominating the field.

Prospective, longitudinal analyses revealed that over a 12-year period from ages 6 to 18, individuals who grew up with mothers with more proenvironmental attitudes engaged in more proenvironmental behavior as young adults. A similar marginal association was uncovered between mothers’ proenvironmental behaviors and the proenvironmental behavior of their young adult offspring. Maternal educational attainment, but not political ideology, was also associated with more proenvironmental behavior as children matured. Moreover, childhood time spent outdoors was positively associated with increased environmentally responsible behavior in young adulthood. Interestingly, one’s own childhood proenvironmental behavior and attitude, at least as assessed at age 6, bear little on one’s eventual proenvironmental behavior as a young adult. Finally, among this set of childhood factors, maternal education and childhood time spent outdoors were independent predictors of positive changes in environmental behavior from early childhood to young adulthood.

People will often rationalize the status quo, reconstruing it in an exaggeratedly positive light. They will even rationalize the status quo they anticipate, emphasizing the upsides and minimizing the downsides of sociopolitical realities they expect to take effect. Drawing on recent findings on the psychological triggers of rationalization, I present results from three field studies, one of which was preregistered, testing the hypothesis that an anticipated reality becoming current triggers an observable boost in people’s rationalizations. San Franciscans rationalized a ban on plastic water bottles, Ontarians rationalized a targeted smoking ban, and Americans rationalized the presidency of Donald Trump, more in the days immediately after these realities became current compared with the days immediately before. Additional findings show evidence for a mechanism underlying these behaviors and rule out alternative accounts. These findings carry implications for scholarship on rationalization, for understanding protest behavior, and for policymakers.

People perceive morality to be distinctively human, with immorality representing a lack of full humanness. In eight experiments, we examined the link between immorality and self-dehumanization, testing both (a) the causal role of immoral behavior on self-dehumanization and (b) the causal role of self-dehumanization on immoral behavior. Studies 1a to 1d showed that people feel less human after behaving immorally and that these effects were not driven by having a negative experience but were unique to experiences of immorality (Study 1d). Studies 2a to 2c showed that self-dehumanization can lead to immoral and antisocial behavior. Study 3 highlighted how self-dehumanization can sometimes produce downward spirals of immorality, demonstrating initial unethical behavior leading to self-dehumanization, which in turn promotes continued dishonesty. These results demonstrate a clear relationship between self-dehumanization and unethical behavior, and they extend previous theorizing on dehumanization.

People differ in how quickly they learn information and how long they remember it, yet individual differences in learning abilities within healthy adults have been relatively neglected. In two studies, we examined the relation between learning rate and subsequent retention using a new foreign-language paired-associates task (the learning-efficiency task), which was designed to eliminate ceiling effects that often accompany standardized tests of learning and memory in healthy adults. A key finding was that quicker learners were also more durable learners (i.e., exhibited better retention across a delay), despite studying the material for less time. Additionally, measures of learning and memory from this task were reliable in Study 1 ( N = 281) across 30 hr and Study 2 ( N = 92; follow-up n = 46) across 3 years. We conclude that people vary in how efficiently they learn, and we describe a reliable and valid method for assessing learning efficiency within healthy adults.

Research over the past decade has shown that various personality traits are communicated through musical preferences. One limitation of that research is external validity, as most studies have assessed individual differences in musical preferences using self-reports of music-genre preferences. Are personality traits communicated through behavioral manifestations of musical preferences? We addressed this question in two large-scale online studies with demographically diverse populations. Study 1 ( N = 22,252) shows that reactions to unfamiliar musical excerpts predicted individual differences in personality—most notably, openness and extraversion—above and beyond demographic characteristics. Moreover, these personality traits were differentially associated with particular music-preference dimensions. The results from Study 2 ( N = 21,929) replicated and extended these findings by showing that an active measure of naturally occurring behavior, Facebook Likes for musical artists, also predicted individual differences in personality. In general, our findings establish the robustness and external validity of the links between musical preferences and personality.

Why do some cultural items become popular? Although some researchers have argued that success is random, we suggest that how similar items are to each other plays an important role. Using natural language processing of thousands of songs, we examined the relationship between lyrical differentiation (i.e., atypicality) and song popularity. Results indicated that the more different a song’s lyrics are from its genre, the more popular it becomes. This relationship is weaker in genres where lyrics matter less (e.g., dance) or where differentiation matters less (e.g., pop) and occurs for lyrical topics but not style. The results shed light on cultural dynamics, why things become popular, and the psychological foundations of culture more broadly.

Charity could do the most good if every dollar donated went to causes that produced the greatest welfare gains. In line with this proposition, the effective-altruism movement seeks to provide individuals with information regarding the effectiveness of charities in hopes that they will contribute to organizations that maximize the social return of their donation. In this research, we investigated the extent to which presenting effectiveness information leads people to choose more effective charities. We found that even when effectiveness information is made easily comparable across options, it has a limited impact on choice. Specifically, people frequently choose less effective charity options when those options represent more subjectively preferred causes. In contrast to making a personal donation decision, outcome metrics are used to a much greater extent when choosing financial investments and when allocating aid resources as an agent of an organization. Implications for effective altruism are discussed.

Children’s early language exposure impacts their later linguistic skills, cognitive abilities, and academic achievement, and large disparities in language exposure are associated with family socioeconomic status (SES). However, there is little evidence about the neural mechanisms underlying the relation between language experience and linguistic and cognitive development. Here, language experience was measured from home audio recordings of 36 SES-diverse 4- to 6-year-old children. During a story-listening functional MRI task, children who had experienced more conversational turns with adults—independently of SES, IQ, and adult-child utterances alone—exhibited greater left inferior frontal (Broca’s area) activation, which significantly explained the relation between children’s language exposure and verbal skill. This is the first evidence directly relating children’s language environments with neural language processing, specifying both an environmental and a neural mechanism underlying SES disparities in children’s language skills. Furthermore, results suggest that conversational experience impacts neural language processing over and above SES or the sheer quantity of words heard.

Persuasion is a foundational topic within psychology, in which researchers have long investigated effective versus ineffective means to change other people’s minds. Yet little is known about how individuals’ communications are shaped by the intent to persuade others. This research examined the possibility that people possess a learned association between emotion and persuasion that spontaneously shifts their language toward more emotional appeals, even when such appeals may be suboptimal. We used a novel quantitative linguistic approach in conjunction with controlled laboratory experiments and real-world data. This work revealed that the intent to persuade other people spontaneously increases the emotionality of individuals’ appeals via the words they use. Furthermore, in a preregistered experiment, the association between emotion and persuasion appeared sufficiently strong that people persisted in the use of more emotional appeals even when such appeals might backfire. Finally, direct evidence was provided for an association in memory between persuasion and emotionality.