Joshua Conrad Jackson

Registered Replication Report

Trying to remember something now typically improves your ability to remember it later. However, after watching a video of a simulated bank robbery, participants who verbally described the robber were 25% worse at identifying the robber in a lineup than were participants who instead listed U.S. states and capitals—this has been termed the “verbal overshadowing” effect (Schooler & Engstler-Schooler, 1990). More recent studies suggested that this effect might be substantially smaller than first reported. Given uncertainty about the effect size, the influence of this finding in the memory literature, and its practical importance for police procedures, we conducted two collections of preregistered direct replications (RRR1 and RRR2) that differed only in the order of the description task and a filler task. In RRR1, when the description task immediately followed the robbery, participants who provided a description were 4% less likely to select the robber than were those in the control condition. In RRR2, when the description was delayed by 20 min, they were 16% less likely to select the robber. These findings reveal a robust verbal overshadowing effect that is strongly influenced by the relative timing of the tasks. The discussion considers further implications of these replications for our understanding of verbal overshadowing.

From one mind to many: the emerging science of cultural norms

Cultural norms permeate human existence. They shape our view of reality and the evolution of culture. In this review, we discuss the benefits of a cultural science that studies norms as well as values, and review research on (a) whether cultural norms are distinctly human, (b) when people will follow cultural norms, and (c) what factors shape the content and strength of cultural norms. We argue that studying cultural norms represents a critical cross-disciplinary, multi-level approach that is ideal for both understanding culture and tapping its potential for positive change.

Agent-based Modeling: A Guide for Social Psychologists

Agent-based modeling is a long-standing but underused method that allows researchers to simulate artificial worlds for hypothesis testing and theory building. Agent-based models (ABMs) offer unprecedented control and statistical power by allowing researchers to precisely specify the behavior of any number of agents and observe their interactions over time. ABMs are especially useful when investigating group behavior or evolutionary processes and can uniquely reveal nonlinear dynamics and emergence—the process whereby local interactions aggregate into often-surprising collective phenomena such as spatial segregation and relational homophily. We review several illustrative ABMs, describe the strengths and limitations of this method, and address two misconceptions about ABMs: reductionism and “you get out what you put in.” We also offer maxims for good and bad ABMs, give practical tips for beginner modelers, and include a list of resources and other models. We conclude with a seven-step guide to creating your own model.

Grand challenges for the study of cultural evolution

The founding members of the Cultural Evolution Society were surveyed to identify the major scientific questions and ‘grand challenges’ currently facing the study of cultural evolution. We present the results and discuss the implications for an emergent synthesis in the study of culture based on Darwinian principles.

Incipient Social Groups: An Analysis via In-Vivo Behavioral Tracking.

Social psychology is fundamentally the study of individuals in groups, yet there remain basic unanswered questions about group formation, structure, and change. We argue that the problem is methodological. Until recently, there was no way to track who was interacting with whom with anything approximating valid resolution and scale. In the current study we describe a new method that applies recent advances in image-based tracking to study incipient group formation and evolution with experimental precision and control. In this method, which we term “in vivo behavioral tracking,” we track individuals’ movements with a high definition video camera mounted atop a large field laboratory. We report results of an initial study that quantifies the composition, structure, and size of the incipient groups. We also apply in-vivo spatial tracking to study participants’ tendency to cooperate as a function of their embeddedness in those crowds. We find that participants form groups of seven on average, are more likely to approach others of similar attractiveness and (to a lesser extent) gender, and that participants’ gender and attractiveness are both associated with their proximity to the spatial center of groups (such that women and attractive individuals are more likely than men and unattractive individuals to end up in the center of their groups). Furthermore, participants’ proximity to others early in the study predicted the effort they exerted in a subsequent cooperative task, suggesting that submergence in a crowd may predict social loafing. We conclude that in vivo behavioral tracking is a uniquely powerful new tool for answering longstanding, fundamental questions about group dynamics.

Perceived Openness to Experience Accounts for Religious Homogamy

Two studies tested the hypothesis that religious homogamy—assortative mating on the basis of religion—can be partly explained by inferences about religious individuals’ openness to experience, rather than attitudes toward religion per se. Results of Study 1 indicated that non-religious participants perceived non-religious targets to be higher in openness and more appealing as romantic partners, with the first effect statistically accounting for the second. Study 2, which manipulated “religious” and “open” behaviors independently, showed that openness guided dating judgments for both non-religious and religious participants, albeit in opposite directions. Thus, regardless of their own religious beliefs, individuals appear to infer the same kind of behaviors from others’ religiosity, behaviors that are seen positively by religious individuals, but negatively by non-religious individuals. These inferences, in turn, partially explain all individuals’ preferences for partners of the same religious orientation.

Testing the causal relationship between religious belief and death anxiety

ABSTRACT Religion has long been speculated to function as a strategy to ameliorate our fear of death. Terror management theory provides two possible causal pathways through which religious beliefs can fulfil this function. According to the “worldview defence” account of terror management, worldviews reduce death anxiety by offering symbolic immortality: on this view, only people who accept the religious worldview in question should benefit from religious beliefs. Alternatively, religious worldviews also offer literal immortality, and may do so independently of individuals’ worldviews. Both strands of thought appear in the terror management theory literature. In this paper, we attempt to resolve this issue experimentally by manipulating religious belief and measuring explicit (Study 1) and implicit (Study 2) death anxiety. In Study 1, we found that the effect of religious belief on explicit death anxiety depends critically on participants’ own religious worldviews, such that believers and non-believers reported greater death anxiety when their worldview is threatened. In Study 2, however, we find that religious belief alleviates implicit death anxiety amongst both believers and non-believers. These findings suggest that religious beliefs can alleviate death anxiety at two different levels, by offering symbolic and literal immortality, respectively.

The Strength of Social Norms Across Human Groups

Social norms are a defining feature of human psychology, yet our understanding of them is still underdeveloped. In this article, we present our own cross-cultural research program on tightness-looseness (TL)—which draws on field, experimental, computational, and neuroscience methods—to illustrate how going beyond Western borders is critical for understanding social norms’ functions and their multilevel consequences. Cross-cultural research enables us to account for the universal features of norm psychology but also explains the great cultural diversity we see in social norms around the globe.

Strangers in a Stadium: Studying Group Dynamics With In Vivo Behavioral Tracking

Social group dynamics are a defining topic of psychological science, yet the field still lacks methods of tracking groups with precision and control. Previous methods have been hampered by limitations either to external validity (e.g., ecologically deficient environments) or to internal validity (e.g., quasi-experimental designs), but a new technique—which we term in vivo behavioral tracking (IBT)—resolves this trade-off. Through IBT, we track large numbers of people in controlled environments over time, while storing precise behavioral data that can be linked to information regarding participants’ attitudes, personality, and demographics. In this article, we describe the fundamentals, assumptions, and challenges of IBT methodology. We also compare IBT to other tracking methods and illustrate some insights it has provided into group formation and cooperation. We argue that IBT is a highly valid and surprisingly feasible method of studying groups that should be used alongside more traditional forms of data collection.

Synchrony and Physiological Arousal Increase Cohesion and Cooperation in Large Naturalistic Groups

Separate research streams have identified synchrony and arousal as two factors that might contribute to the effects of human rituals on social cohesion and cooperation. But no research has manipulated these variables in the field to investigate their causal – and potentially interactive – effects on prosocial behaviour. Across four experimental sessions involving large samples of strangers, we manipulated the synchronous and physiologically arousing affordances of a group marching task within a sports stadium. We observed participants’ subsequent movement, grouping, and cooperation via a camera hidden in the stadium’s roof. Synchrony and arousal both showed main effects, predicting larger groups, tighter clustering, and more cooperative behaviour in a free-rider dilemma. Synchrony and arousal also interacted on measures of clustering and cooperation such that synchrony only encouraged closer clustering—and encouraged greater cooperation—when paired with physiological arousal. The research helps us understand why synchrony and arousal often co-occur in rituals around the world. It also represents the first use of real-time spatial tracking as a precise and naturalistic method of simulating collective rituals.