David Pietraszewski

The Content of Our Cooperation, Not the Color of Our Skin: An Alliance Detection System Regulates Categorization by Coalition and Race, but Not Sex

Humans in all societies form and participate in cooperative alliances. To successfully navigate an alliance-laced world, the human mind needs to detect new coalitions and alliances as they emerge, and predict which of many potential alliance categories are currently organizing an interaction. We propose that evolution has equipped the mind with cognitive machinery that is specialized for performing these functions: an alliance detection system. In this view, racial categories do not exist because skin color is perceptually salient; they are constructed and regulated by the alliance system in environments where race predicts social alliances and divisions. Early tests using adversarial alliances showed that the mind spontaneously detects which individuals are cooperating against a common enemy, implicitly assigning people to rival alliance categories based on patterns of cooperation and competition. But is social antagonism necessary to trigger the categorization of people by alliance—that is, do we cognitively link A and B into an alliance category only because they are jointly in conflict with C and D? We report new studies demonstrating that peaceful cooperation can trigger the detection of new coalitional alliances and make race fade in relevance. Alliances did not need to be marked by team colors or other perceptually salient cues. When race did not predict the ongoing alliance structure, behavioral cues about cooperative activities up-regulated categorization by coalition and down-regulated categorization by race, sometimes eliminating it. Alliance cues that sensitively regulated categorization by coalition and race had no effect on categorization by sex, eliminating many alternative explanations for the results. The results support the hypothesis that categorizing people by their race is a reversible product of a cognitive system specialized for detecting alliance categories and regulating their use. Common enemies are not necessary to erase important social boundaries; peaceful cooperation can have the same effect.

Priming Race Does the Mind Inhibit Categorization by Race at Encoding or Recall

Recent research shows that racial categorization can be reduced by contexts in which race does not predict how people interact and get along—a manipulation with little to no effect on sex and age. This suggests that our minds attend to race as an implicit cue to how people are likely to get along. However, the underlying mechanism of how these contexts reduce race is not yet known. Is race not encoded? Or, is race encoded, but then inhibited? The present study arbitrates between these possibilities. Results demonstrate that the reduction in racial categorization is happening at recall. Participants are still encoding targets’ race, but this information is locked away or inhibited. This clarifies how the mind switches away from previously relevant, but now irrelevant, social cues: it does not immediately abandon them, rather, it encodes them but inhibits their use.

The elementary dynamics of intergroup conflict and revenge.

The psychology underlying revenge in an intergroup context is built around a small handful of recurrent interaction types. Analyzing the cost/benefit calculations of each agent’s role within these interaction types provides a more precise way to characterize intergroup conflict and revenge. This in turn allows for more precise models of the psychology of intergroup conflict to be proposed and tested.

Three-month-old-human infants use vocal cues of body size

Differences in vocal fundamental (F0) and average formant (Fn) frequencies covary with body size in most terrestrial mammals, such that larger organisms tend to produce lower frequency sounds than smaller organisms, both between species and also across different sex and life-stage morphs within species. Here we examined whether three-month-old human infants are sensitive to the relationship between body size and sound frequencies. Using a violation-of-expectation paradigm, we found that infants looked longer at stimuli inconsistent with the relationship—that is, a smaller organism producing lower frequency sounds, and a larger organism producing higher frequency sounds—than at stimuli that were consistent with it. This effect was stronger for fundamental frequency than it was for average formant frequency. These results suggest that by three months of age, human infants are already sensitive to the biologically relevant covariation between vocalization frequencies and visual cues to body size. This ability may be a consequence of developmental adaptations for building a phenotype capable of identifying and representing an organisms size, sex and life-stage.

What is argument for? An adaptationist approach to argument and debate

A consideration of selection pressures on the psychology of argument suggests that fixing the truth value of claims is not the primary criterion for argument generation or evaluation. Instead, argument psychology is designed to change representations in other minds as a way to negotiate conflicts of interest and as a way to signal social coordination.