Letters

Despite being a major cultural group, Arabs are relatively neglected in cultural psychology. Going beyond the prevailing East versus West paradigm, this paper suggests that a unique form of interdependence that is self-assertive typifies Arab culture.

Analyses of data from 211 independent, randomized controlled trials (N = 16,198,595) show that second-order normative beliefs—community members’ belief that saving energy helps the environment—play a critical role in promoting energy conservation.

Siegel et al. describe an asymmetric Bayesian updating mechanism for moral impression formation, which shows that beliefs about badly behaved agents are more uncertain and therefore more flexible than beliefs about well-behaved agents.

Gerlach and colleagues harness the power of big data to address the question of whether individuals can be reliably classified into personality types and how many types exist. The authors identify four different personality types, which surface across data sets.

Thomas and colleagues show that toddlers preferred a puppet that had won a conflict against another puppet—but only when it won without using force. This suggests that toddlers consider social status when making social evaluations.

In a compound climate change dilemma that allows some to earn a pre-game advantage, advantaged participants act prosocially later to maintain a public good, but the disadvantaged act antisocially, creating conflict that reduces cooperative success.

People differ in how they cope with task complexity and time constraints. Eldar et al. use magnetoencephalography to show that these differences can be explained by the temporal organization of a neural information integration process.

Brain networks are characterized by nodes and hubs that determine information flow within and between areas. Bertolero et al. show that task-driven changes to hub and node connectivity increase modularity and improve cognitive performance.

Camerer et al. carried out replications of 21 Science and Nature social science experiments, successfully replicating 13 out of 21 (62%). Effect sizes of replications were about half of the size of the originals.

Akbarzadeh and Estrada mathematically characterize the properties of traffic flow and find that, in four different cities, there is more traffic not through the shortest paths, but through the communicability shortest paths, which assume an ‘all-routes’ flow.

A study of intimate partner violence among the Tsimané forager-horticulturalists of Bolivia finds evidence that male aggression is leveraged to increase marital fertility and a man’s individual fitness when spouses differ in preferred family size.

Humans can recognize emotions from facial expressions. Brooks and Freeman investigate the link between conceptual representation and visual perception of emotions and show that emotions that are represented as conceptually similar are perceived as similar.

Theories about the spread of Christianity are tested using comparative cross-cultural methods and historical data on 70 Austronesian cultures. Conversion was fastest in small and politically organized societies, but not impacted by social inequality.

Shortly after retrieval, memory undergoes a labile period during which it can be modified. This study shows that this reconsolidation phase shows the same behavioural and neural characteristics as the initial learning phase.

Experiments using economic games and hypothetical infectious disease scenarios show that uncertainty about a decision’s outcome reduces prosocial actions, but when the impact on others is made uncertain, prosociality increases.

Analyses of twin and genomic data show a significant influence of genetic factors on the co-development of conduct and emotional problems from childhood to adolescence. Those with co-developing symptoms may represent a clinical subgroup with higher genetic risk.

Category learning has been traditionally viewed as a high-level cognitive process independent of sensory systems. Rosedahl and colleagues demonstrate that procedural category learning is in fact dependent on low-level visual representations.

Through mathematical analysis, simulations and examples from real-world social networks, Fotouhi et al. demonstrate how establishing sparse interconnections between previously segregated, uncooperative societies can support the evolution of cooperation globally.

Analysing high-resolution mobility traces from almost 40,000 individuals reveals that people typically revisit a set of 25 familiar locations day-to-day, but that this set evolves over time and is proportional to the size of their social sphere.

Kaplan and colleagues find that, in virtual foraging environments in which resource availability is variable, over time, tolerated theft of the resources of others declines, as participants endogenously develop reciprocal exchange relationships to buffer risk.