Emotions before actions: When children see costs as causal

Adults expect people to be biased by sunk costs, but young children do not. We tested between two accounts for why children overlook the sunk cost bias. On one account, children do not see sunk costs as causal. The other account posits that children see sunk costs as causal, but unlike adults, think future actions cannot make up for sunk costs. These accounts make opposing predictions about whether children should see sunk costs as affecting emotions. Across three experiments, 4-7-year-olds (total N = 320) and adults (total N = 429) saw stories about characters who collected items that were easy or difficult to obtain, and predicted characters' emotions and actions. At all ages, participants anticipated that characters would feel sadder about high-cost objects, but only adults predicted that characters would keep high-cost objects. Our findings show that children see incurred costs as causal, and that costs are integrated children's and adults' theory of emotions. Moreover, the findings suggest that developmental differences in sunk cost reasoning may rest in children's incomplete mental accounting. We also discuss children's reasoning about rational and irrational action.

Variation in pedagogy affects overimitation in children and adolescents

Children are strong imitators, which sometimes leads to overimitation of causally unnecessary actions. Here, we tested whether learning from a peer decreases this tendency. First, 65 7- to 10-year-old children performed the Hook task (i.e., retrieve a reward from a jar with tools) with child or adult demonstrators. The overimitation rate was lower after watching a peer versus an adult. Second, we tested whether experiencing peer-to-peer learning versus adult-driven learning (i.e., Montessori or traditional pedagogy) affected overimitation. Here, 66 4- to 18-year-old children and adolescents performed the Hook task with adult demonstrators only. Montessori-schooled children had a lower propensity to overimitate. These findings emphasize the importance of the teaching model across the school years. Whereas peer models favor selective imitation, adult models encourage overimitation.

Do children imitate even when it is costly? New insights from a novel task

Children have a proclivity to learn through faithful imitation, but the extent to which this applies under significant cost remains unclear. To address this, we investigated whether 4- to 6-year-old children (N = 97) would stop imitating to forego a desirable food reward. We presented participants with a task involving arranging marshmallows and craft sticks, with the goal being either to collect marshmallows or build a tower. Children replicated the demonstrated actions with high fidelity regardless of the goal, but retrieved rewards differently. Children either copied the specific actions needed to build a tower, prioritizing tower completion over reward; or adopted a novel convention of stacking materials before collecting marshmallows, and developed their own method to achieve better outcomes. These results suggest children's social learning decisions are flexible and context-dependent, yet that when framed by an ostensive goal, children imitated in adherence to the goal despite incurring significant material costs.

Children's distinct drive to reproduce costly rituals

Costly rituals are ubiquitous and adaptive. Yet, little is known about how children develop to acquire them. The current study examined children's imitation of costly rituals. Ninety-three 4-6 year olds (47 girls, 45% Oceanians, tested in 2022) were shown how to place tokens into a tube to earn stickers, using either a ritualistic or non-ritualistic costly action sequence. Children shown the ritualistic actions imitated faithfully at the expense of gaining stickers; conversely, those shown the non-ritualistic actions ignored them and obtained maximum reward. This highlights how preschool children are adept at and motivated to learn rituals, despite significant material cost. This study provides insights into the early development of cultural learning and the adaptive value of rituals in group cognition.

Defining collective irrationality of COVID-19: shared mentality, mimicry, affective contagion, and psychosocial adaptivity

This paper defines the nature of collective irrationality that flourished during the COVID-19 pandemic and lays out specific individual and shared traits and dispositions that facilitate it. Drawing on the example of globally experienced phenomenon of panicked toilet paper buying and hoarding during the COVID-19 pandemic and resources from philosophy, psychology, sociology, and economics this paper identifies four essential features of collective irrationality: weak shared mentality; non-cognitive and immediate mimicry; affective contagion; and psychosocial adaptivity. After (I) initially pointing out conceptual problems around benchmarking collectivity and irrationality, this paper (II) identifies weak mentality as serving the goals of "group" recognition internally and externally. It is argued that (III) the non-cognitive and immediate mimicry and emotional contagion are shared and individual dispositional conditions that facilitate collective irrationality in environments affected by uncertainty (IV). The human mimetic faculty and susceptibility to emotional contagion are presented as enabling and augmenting conditions under which collective irrationality flourishes. Finally, (IV) presenting collective irrationality in the context of psychosocial adaptivity, the paper provides evolutionary reasons for engaging in irrational behaviors, rendering collective irrationality as an adaptive strategy.

Not Playing by the Rules: Exploratory Play, Rational Action, and Efficient Search

Recent studies suggest children's exploratory play is consistent with formal accounts of rational learning. Here we focus on the tension between this view and a nearly ubiquitous feature of human play: In play, people subvert normal utility functions, incurring seemingly unnecessary costs to achieve arbitrary rewards. We show that four-and-five-year-old children not only infer playful behavior from observed violations of rational action (Experiment 1), but themselves take on unnecessary costs during both retrieval (Experiment 2) and search (Experiments 3A-B) tasks, despite acting efficiently in non-playful, instrumental contexts. We discuss the value of such apparently utility-violating behavior and why it might serve learning in the long run.

Ecological Values Theory: Beyond Conformity, Goal-Seeking, and Rule-Following in Action and Interaction

Values have long been considered important for psychology but are frequently characterized as beliefs, goals, rules, or norms. Ecological values theory locates them, not in people or in objects, but in ecosystem relationships and the demands those relationships place on fields of action within the system. To test the worth of this approach, we consider skilled coordination tasks in social psychology (e.g., negotiating disagreements, synchrony and asynchrony in interactions, and selectivity in social learning) and perception-action (e.g., driving vehicles and carrying a child). Evidence suggests that a diverse array of values (e.g., truth, social solidarity, justice, flexibility, safety, and comfort) work in a cooperative tension to guide actions. Values emerge as critical constraints on action that differ from goals, rules, and natural laws, and yet provide the larger context in which they can function effectively. Prospects and challenges for understanding values and their role in action, including theoretical and methodological issues, are considered.

Plans or Outcomes: How Do We Attribute Intelligence to Others?

Humans routinely make inferences about both the contents and the workings of other minds based on observed actions. People consider what others want or know, but also how intelligent, rational, or attentive they might be. Here, we introduce a new methodology for quantitatively studying the mechanisms people use to attribute intelligence to others based on their behavior. We focus on two key judgments previously proposed in the literature: judgments based on observed outcomes (you're smart if you won the game) and judgments based on evaluating the quality of an agent's planning that led to their outcomes (you're smart if you made the right choice, even if you didn't succeed). We present a novel task, the maze search task (MST), in which participants rate the intelligence of agents searching a maze for a hidden goal. We model outcome-based attributions based on the observed utility of the agent upon achieving a goal, with higher utilities indicating higher intelligence, and model planning-based attributions by measuring the proximity of the observed actions to an ideal planner, such that agents who produce closer approximations of optimal plans are seen as more intelligent. We examine human attributions of intelligence in three experiments that use MST and find that participants used both outcome and planning as indicators of intelligence. However, observing the outcome was not necessary, and participants still made planning-based attributions of intelligence when the outcome was not observed. We also found that the weights individuals placed on plans and on outcome correlated with an individual's ability to engage in cognitive reflection. Our results suggest that people attribute intelligence based on plans given sufficient context and cognitive resources and rely on the outcome when computational resources or context are limited.

Understanding Human Cognitive Uniqueness

Humanity has regarded itself as intellectually superior to other species for millennia, yet human cognitive uniqueness remains poorly understood. Here, we evaluate candidate traits plausibly underlying our distinctive cognition (including mental time travel, tool use, problem solving, social cognition, and communication) as well as domain generality, and we consider how human cognitive uniqueness may have evolved. We conclude that there are no traits present in humans and absent in other animals that in isolation explain our species' superior cognitive performance; rather, there are many cognitive domains in which humans possess unusually potent capabilities compared to those found in other species. Humans are flexible cognitive all-rounders, whose proficiency arises through interactions and reinforcement between cognitive domains at multiple scales.