A multi-lab test of the facial feedback hypothesis by the Many Smiles Collaboration.

Following theories of emotional embodiment, the facial feedback hypothesis suggests that individuals' subjective experiences of emotion are influenced by their facial expressions. However, evidence for this hypothesis has been mixed. We thus formed a global adversarial collaboration and carried out a preregistered, multicentre study designed to specify and test the conditions that should most reliably produce facial feedback effects. Data from n = 3,878 participants spanning 19 countries indicated that a facial mimicry and voluntary facial action task could both amplify and initiate feelings of happiness. However, evidence of facial feedback effects was less conclusive when facial feedback was manipulated unobtrusively via a pen-in-mouth task.

Psychological distress mediates the connection between sleep deprivation and physical fighting in adolescents.

Lack of sleep is common in adolescence, and represents an important threat to adolescents' well-being, academic commitment, and general health. It also has significant behavioral consequences through an increased likelihood of interpersonal violence. Previous studies have demonstrated an association between aggressive behavior and lack of sleep, but the psychological mediators remain completely unexplored. Grounded in the General Aggression Model, we investigated the affective pathway as one of the potential mechanisms linking lack of sleep and aggression. We hypothesized and showed that psychological distress is an intermediary phenomenon linking lack of sleep and physical aggression. Based on a school sample of 11,912 participants (median age: 14.5), we observed that 23.7% of the young people admitted having been involved in physical fighting on one or more occasions, and that 25.81% were in sleep debt when referred for medical assessment. We analyzed the relationship between sleep duration and physical fighting and the mediating link of psychological distress by performing multiple regressions in the components' paths. The results showed that the adolescents' amount of sleep appeared to be a significant predictor of physical fighting, and that this relationship was partially mediated by psychological distress. These results are consistent with the General Aggression Model, and represent the first empirical confirmation that psychological distress symptoms partially mediate the connection between lack of sleep and physical aggression.

Authoritarian attitudes are associated with higher autonomic reactivity to stress and lower recovery.

Right-wing authoritarianism (RWA) and social dominance orientation (SDO) both predict generalized prejudice, dehumanization, intergroup discrimination, oppression, violence, right-wing political party preference, and generally punitive attitudes. Authoritarian attitudes have been theorized to involve maladaptive emotional, cognitive, and social self-regulation. However, there is no study of authoritarianism using the functioning of the parasympathetic nervous system (PNS) as a physiological index of self-regulation, thus leaving it unclear whether regulation is "impaired" with authoritarian attitudes per se. PNS functioning is commonly assessed by examining tonic and phasic heart rate variability (HRV). These two components are recognized to be important in terms of adaptation to stress. Decreased HRV has been associated with hypoactive prefrontal regulation, hyperactive subcortical structures, maladaptive self-regulation, hyper-vigilance, decreased prosocial tendencies, defensiveness, impulsive behaviors, and aggression. Previous research suggests that self-regulatory failure may favor hostile attitudes and prejudicial intergroup behaviors. In a first study, we found that high RWA was associated with lower tonic HRV at rest. In a second study, stress-induced autonomic reactivity and poststress autonomic recovery were examined as potential pathways linking authoritarian attitudes to self-regulation. We found that high RWA and high SDO were associated with (i) lower tonic HRV during stress, (ii) greater autonomic reactivity during stress, and (iii) lower autonomic recovery. Overall, our results suggest that autonomic dysregulation during and following stress is a plausible physiological pathway connecting RWA and SDO to self-regulation. Implications of such results for research on political attitudes are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Sacrificing Animals in the Name of Scientific Authority: The Relationship Between Pro-Scientific Mindset and the Lethal Use of Animals in Biomedical Experimentation.

The present research investigated how scientific authority increases the lethal use of animals in biomedical experimentation. In two behavioral studies (N = 151 and 150), participants were required to incrementally administer 12 doses of a toxic chemical to a 53-cm fish (in reality, a biomimetic robot) for research on animal learning. Consistent with the Engaged Followership Theory on obedience, participants placed in a pro-scientific mindset more severely harmed the laboratory animal. In a cross-sectional study (N = 351), participants in medical fields endorsed a more pro-scientific attitude than those in paramedical fields, which mediated their support for animal experimentation. Drawing on a representative European sample (N = 31,238), we also confirmed the specificity of this link by controlling for potential demographic and ideological confounds. In a final study (N = 1,598), instrumental harm was shown as mediating the link between a pro-scientific attitude and support for animal experimentation.