Social-rank cues: Decoding rank from physical characteristics, behaviors, and possessions

The Effect of Income and Wealth on Behavioral Strategies, Personality Traits, and Preferences

Individuals living in either harsh or favorable environments display well-documented psychological and behavioral differences. For example, people in favorable environments tend to be more future-oriented, trust strangers more, and have more explorative preferences. To account for such differences, psychologists have turned to evolutionary biology and behavioral ecology, in particular, the literature on life-history theory and pace-of-life syndrome. However, critics have found that the theoretical foundations of these approaches are fragile and that differences in life expectancy cannot explain vast psychological and behavioral differences. In this article, we build on the theory of optimal resource allocation to propose an alternative framework. We hypothesize that the quantity of resources available, such as income, has downstream consequences on psychological traits, leading to the emergence of behavioral syndromes. We show that more resources lead to more long-term orientation, more tolerance of variance, and more investment in low marginal-benefit needs. At the behavioral level, this translates, among others, into more large-scale cooperation, more investment in health, and more exploration. These individual-level differences in behavior, in turn, account for cultural phenomena such as puritanism, authoritarianism, and innovation.

Cortical astrocytes modulate dominance behavior in male mice by regulating synaptic excitatory and inhibitory balance

Social hierarchy is established as an outcome of individual social behaviors, such as dominance behavior during long-term interactions with others. Astrocytes are implicated in optimizing the balance between excitatory and inhibitory (E/I) neuronal activity, which may influence social behavior. However, the contribution of astrocytes in the prefrontal cortex to dominance behavior is unclear. Here we show that dorsomedial prefrontal cortical (dmPFC) astrocytes modulate E/I balance and dominance behavior in adult male mice using in vivo fiber photometry and two-photon microscopy. Optogenetic and chemogenetic activation or inhibition of dmPFC astrocytes show that astrocytes bidirectionally control male mouse dominance behavior, affecting social rank. Dominant and subordinate male mice present distinct prefrontal synaptic E/I balance, regulated by astrocyte activity. Mechanistically, we show that dmPFC astrocytes control cortical E/I balance by simultaneously enhancing presynaptic-excitatory and reducing postsynaptic-inhibitory transmission via astrocyte-derived glutamate and ATP release, respectively. Our findings show how dmPFC astrocyte-neuron communication can be involved in the establishment of social hierarchy in adult male mice.

Status-impact assessment: is accuracy linked with status motivations?

Status hierarchies are ubiquitous across cultures and have been over deep time. Position in hierarchies shows important links with fitness outcomes. Consequently, humans should possess psychological adaptations for navigating the adaptive challenges posed by living in hierarchically organised groups. One hypothesised adaptation functions to assess, track, and store the status impacts of different acts, characteristics and events in order to guide hierarchy navigation. Although this status-impact assessment system is expected to be universal, there are several ways in which differences in assessment accuracy could arise. This variation may link to broader individual difference constructs. In a preregistered study with samples from India (N = 815) and the USA (N = 822), we sought to examine how individual differences in the accuracy of status-impact assessments covary with status motivations and personality. In both countries, greater overall status-impact assessment accuracy was associated with higher status motivations, as well as higher standing on two broad personality constructs: Honesty-Humility and Conscientiousness. These findings help map broad personality constructs onto variation in the functioning of specific cognitive mechanisms and contribute to an evolutionary understanding of individual differences.