Logically, group members cannot be responsible for more than 100% of the group's output, yet claims of responsibility routinely sum to more than 100%. This "over-claiming" occurs partly because of egocentrism: People focus on their own contributions, as focal members of the group, more than on others' contributions. Therefore, we predicted that over-claiming would increase with group size because larger groups leave more contributions from others to overlook. In 2 field studies, participants claimed more responsibility as the number of academic authors per article and the number of MBA students per study group increased. As predicted by our theoretical account, this over-claiming bias was reduced when group members considered others' contributions explicitly. Two experiments that directly manipulated group size replicated these results. Members of larger groups may be particularly well advised to consider other members' contributions before considering their own. (PsycINFO Database Record

Police departments use body-worn cameras (body cams) and dashboard cameras (dash cams) to monitor the activity of police officers in the field. Video from these cameras informs review of police conduct in disputed circumstances, often with the goal of determining an officer's intent. Eight experiments (N = 2,119) reveal that body cam video of an incident results in lower observer judgments of intentionality than dash cam video of the same incident, an effect documented with both scripted videos and real police videos. This effect was due, in part, to variation in the visual salience of the focal actor: the body cam wearer is typically less visually salient when depicted in body versus dash cam video, which corresponds with lower observer intentionality judgments. In showing how visual salience of the focal actor may introduce unique effects on observer judgment, this research establishes an empirical platform that may inform public policy regarding surveillance of police conduct.

Human languages typically employ a variety of spatial metaphors for time (e.g., "I'm looking forward to the weekend"). The metaphorical grounding of time in space is also evident in gesture. The gestures that are performed when talking about time bolster the view that people sometimes think about regions of time as if they were locations in space. However, almost nothing is known about the development of metaphorical gestures for time, despite keen interest in the origins of space-time metaphors. In this study, we examined the gestures that English-speaking 6-to-7-year-olds, 9-to-11-year-olds, 13-to-15-year-olds, and adults produced when talking about time. Participants were asked to explain the difference between pairs of temporal adverbs (e.g., "tomorrow" versus "yesterday") and to use their hands while doing so. There was a gradual increase across age groups in the propensity to produce spatial metaphorical gestures when talking about time. However, even a substantial majority of 6-to-7-year-old children produced a spatial gesture on at least one occasion. Overall, participants produced fewer gestures in the sagittal (front-back) axis than in the lateral (left-right) axis, and this was particularly true for the youngest children and adolescents. Gestures that were incongruent with the prevailing norms of space-time mappings among English speakers (leftward and backward for past; rightward and forward for future) gradually decreased with increasing age. This was true for both the lateral and sagittal axis. This study highlights the importance of metaphoricity in children's understanding of time. It also suggests that, by 6 to 7 years of age, culturally determined representations of time have a strong influence on children's spatial metaphorical gestures.

Adequate pain management is one of the biggest challenges of the modern healthcare system. Physician perception of patient subjective pain, which is crucial to pain management, is susceptible to a host of potential biases. Here we explore the timing of physicians' work as a previously unrecognized source of systematic bias in pain management. We hypothesized that during night shifts, sleep deprivation, fatigue, and stress would reduce physicians' empathy for others' pain, leading to underprescription of analgesics for patient pain relief. In study 1, 67 resident physicians, either following a night shift or not, performed empathy for pain assessment tasks and simulated patient scenarios in laboratory conditions. As predicted, following a night shift, physicians showed reduced empathy for pain. In study 2, we explored this phenomenon in medical decisions in the field. We analyzed three emergency department datasets from Israel and the United States that included discharge notes of patients arriving with pain complaints during 2013 to 2020 (n = 13,482). Across all datasets, physicians were less likely to prescribe an analgesic during night shifts (compared to daytime shifts) and prescribed fewer analgesics than generally recommended by the World Health Organization. This effect remained significant after adjusting for patient, physician, type of complaint, and emergency department characteristics. Underprescription for pain during night shifts was particularly prominent for opioids. We conclude that night shift work is an important and previously unrecognized source of bias in pain management, likely stemming from impaired perception of pain. We consider the implications for hospitals and other organizations employing night shifts.