Possession is not always the law: With age, preschoolers increasingly use verbal information to identify who owns what

Children can identify owners either by seeing a person in possession of an object (a visual cue) and inferring that they are the owner or by hearing testimony about a claim of ownership (a verbal cue). A total of 391 children between 2.5 and 6years of age were tested in three experiments assessing how children identify owners when these two cues are in conflict. Children were presented with stories using two dolls and a toy. One doll possessed the toy, and children were told that the toy was either the possessor's or the nonpossessor's. Two forms of ownership statement were used: a third-person statement, "That is Billy's ball", and a first-person statement by one of the dolls, "That is my ball". The results show that by 4years of age, children prioritize the verbal statements as a more reliable cue to ownership than physical possession. Younger children did not prioritize possession over the verbal cue to ownership but rather gave mixed responses. These results are discussed in terms of children's social experience outside of the home and their acceptance of testimony in other domains.     

The effects of reward on tutor's behaviors in a cross-age tutoring context

Utilizing a cross-age tutoring context, this study examined the effects of reward on the teaching behaviors of the tutor, the tutor's subsequent motivation to continue to teach during a free choice period, and the social interaction between a tutor and a tutee. Third-grade boys and girls (n = 96) who exhibited a positive reinforcement style were asked to teach six addition problems to a first-grade boy or girl (n = 96). The children were randomly assigned to pairs and to one of the three reward conditions. In the performance-contingent reward condition, the tutors were promised a toy if the first-grader learned all of the arithmetic problems. In the noncontingent reward condition, the tutors were promised a toy for teaching the first-grader. In the no reward condition, the tutors taught the first-grader without promise of a toy. The results indicated that the social interaction was rated lower for the children in the performance-contingent group and that the tutors in this group spent less time teaching during the free choice period. However, neither the tutor's teaching style nor the tutee's post-test performance was adversely affected by the reward.     

Asymmetry of the group context effect on delay discounting

Binary choice delay discounting tasks require participants to indicate preference between smaller, immediate, and larger, delayed rewards. Previous research indicates that when the delayed reward is shared with others, the delayed outcome is preferred compared with when the outcomes are for the self only, resulting in lower rates of delay discounting. The present series of studies sought to replicate and extend this finding. Study 1 compared delay discounting on a standard task in which both immediate and delayed outcomes are for the self and a group context task where the delayed outcome was shared with one other person. Replicating previous results, group context resulted in lower rates of delay discounting, and this effect was independent of how the shared outcome was presented. Study 2 compared delay discounting on a standard task and a group context task where the immediate outcome was shared. In contrast to Study 1, group context resulted in higher rates of delay discounting, suggesting that preference in intertemporal choice tracks the shared outcome. Moreover, this effect was not independent of how the shared outcome was presented. This is the first study to reveal that group context, when applied to the immediate outcome, can result in higher rates of delay discounting.     

Delay, Probability, and Social Discounting in A Public Goods Game

A human social discount function measures the value to a person of a reward to another person at a given social distance. Just as delay discounting is a hyperbolic function of delay, and probability discounting is a hyperbolic function of odds-against, social discounting is a hyperbolic function of social distance. Experiment 1 obtained individual social, delay, and probability discount functions for a hypothetical $75 reward; participants also indicated how much of an initial $100 endowment they would contribute to a common investment in a public good. Steepness of discounting correlated, across participants, among all three discount dimensions. However, only social and probability discounting were correlated with the public-good contribution; high public-good contributors were more altruistic and also less risk averse than low contributors. Experiment 2 obtained social discount functions with hypothetical $75 rewards and delay discount functions with hypothetical $1,000 rewards, as well as public-good contributions. The results replicated those of Experiment 1; steepness of the two forms of discounting correlated with each other across participants but only social discounting correlated with the public-good contribution. Most participants in Experiment 2 predicted that the average contribution would be lower than their own contribution.     

Let's chat: developmental neural bases of social motivation during real‐time peer interaction

Humans are motivated to interact with each other, but the neural bases of social motivation have been predominantly examined in non‐interactive contexts. Understanding real‐world social motivation is of special importance during middle childhood (ages 8–12), a period when social skills improve, social networks grow, and social brain networks specialize. To assess interactive social motivation, the current study used a novel fMRI paradigm in which children believed they were chatting with a peer. The design targeted two phases of interaction: (1) Initiation, in which children engaged in a social bid via sharing a like or hobby, and (2) Reply, in which children received either an engaged (“Me too”) or non‐engaged (“I'm away”) reply from the peer. On control trials, children were told that their answers were not shared and that they would receive either engaged (“Matched”) or non‐engaged (“Disconnected”) replies from the computer. Results indicated that during Initiation and Reply, key components of reward circuitry (e.g., ventral striatum) were more active for the peer than the computer trials. In addition, during Reply, social cognitive regions were more activated by the peer, and this social cognitive specialization increased with age. Finally, the effect of engagement type on reward circuitry activation was larger for social than non‐social trials, indicating developmental sensitivity to social contingency. These findings demonstrate that both reward and social cognitive brain systems support real‐time social interaction in middle childhood. An interactive approach to understanding social reward has implications for clinical disorders, where social motivation is more affected in real‐world contexts.     

DISCOUNTING OF DELAYED FOOD REWARDS IN PIGEONS AND RATS: IS THERE A MAGNITUDE EFFECT?

Temporal discounting refers to the decrease in the present, subjective value of a reward as the time to its receipt increases. Results from humans have shown that a hyperbola-like function describes the form of the discounting function when choices involve hypothetical monetary rewards. In addition, magnitude effects have been reported in which smaller reward amounts are discounted more steeply than larger amounts. The present research examines the cross-species generality of these findings using real rewards, namely food pellets, with both pigeons and rats. As with humans, an adjusting amount procedure was used to estimate the amount of immediate reward judged equal in value to a delayed reward. Different amounts of delayed food rewards (ranging from 5 to 32 pellets in pigeons and from 5 to 20 pellets in rats) were studied at delays varying from 1 s to 32 s. A simple hyperbola, similar to the hyperbola-like mathematical function that describes the discounting of hypothetical monetary rewards in humans, described the discounting of food rewards in both pigeons and rats. These results extend the generality of the mathematical model of discounting. Rates of discounting delayed food rewards were higher for pigeons than for rats. Unlike humans, however, neither pigeons nor rats showed a reliable magnitude effect: Rate of discounting did not vary systematically as a function of the amount of the delayed reward.     

Age‐related differences in delay discounting: Immediate reward,reward magnitude,and social influence

Delay discounting refers to the tendency of individuals to subjectively devalue rewards that are to be received in the future, with high rates of delay discounting being associated with a variety of maladaptive life outcomes (e.g., unhealthy dietary and exercise behaviors). The current study explored the psychological and social processes involved in adult age‐related differences in delay discounting of monetary rewards. Younger adults exhibited higher levels of delay discounting than older adults. This increased level of patience in older adults was found whether smaller‐sooner rewards were to be received immediately or in the future. However, there was an interaction with reward magnitude, whereby younger adults exhibited higher levels of delay discounting for smaller reward magnitudes but not larger reward magnitudes. Social influence on delay discounting was investigated by having participants complete three phases of the delay‐discounting task: an individual precollaboration phase, a collaboration phase in age‐group‐matched dyads, and an individual postcollaboration phase. A convergence effect was observed in that dyad members' postcollaboration choices were significantly more similar compared to their baseline choices during the precollaboration phase. Moreover, levels of convergence were comparable between younger and older adults, suggesting age invariance in social influence on delay discounting. The current results demonstrate a degree of malleability in delay discounting that extends into older adulthood, making interventions targeting the construct a promising avenue for future research.     

Children's working understanding of knowledge sources: Confidence in knowledge gained from testimony

In three experiments, children aged between 3 and 5 years (N = 38, 52, 94; mean ages 3–7 to 5–2) indicated their confidence in their knowledge of the identity of a hidden toy. With the exception of some 3-year-olds, children revealed working understanding of their knowledge source by showing high confidence when they had seen or felt the toy, and lower confidence when they had been told its identity by an apparently well-informed speaker. Correct explicit source reports were not necessary for children to show relative uncertainty when the speaker subsequently doubted the adequacy of his access to the toy. After a 2-min delay, 3–4-year-olds, unlike 4–5-year-olds, failed to see the implications of the speaker's doubt about his access.     

The absence of numbers to express the amount may affect delay discounting with humans

Human delay discounting is usually studied with experimental protocols that use symbols to express delay and amount. In order to further understand discounting, we evaluated whether the absence of numbers to represent reward amounts affects discount rate in general, and whether the magnitude effect is generalized to nonsymbolic situations in particular. In Experiment 1, human participants were exposed to a delay‐discounting task in which rewards were presented using dots to represent monetary rewards (nonsymbolic); under this condition the magnitude effect did not occur. Nevertheless, the magnitude effect was observed when equivalent reward amounts were presented using numbers (symbolic). Moreover, in estimation tasks, magnitude increments produced underestimation of large amounts. In Experiment 2, participants were exposed only to the nonsymbolic discounting task and were required to estimate reward amounts in each trial. Consistent with Experiment 1, the absence of numbers representing reward amounts produced similar discount rates of small and large rewards. These results suggest that value of nonsymbolic rewards is a nonlinear function of amount and that value attribution depends on perceived difference between the immediate and the delayed nonsymbolic rewards.     

Sex-Stereotyped and Nonstereotyped Introductions of New Toys in the Preschool Classroom: An Observational Study of Teacher Behavior and Its Effects

In Study 1, the behavior of teachers in introducing sex-typed and nonsex-typed toys in the classroom was observed in nine preschool classes. Results indicated that teachers called on more boys to demonstrate a "masculine" toy than girls, p<01. No significant differences were found in the mean number of boys and girls called on to demonstrate "neutral" or "feminine" toys. However, teachers were more variable in demonstrating the sex-typed feminine toys than the nonstereotyped toy, p<05. In a second study, two sets of toys, each including five dolls and five trucks, were introduced using stereotyped and nonstereotyped introductions to two classes of 3- and 4-year-old children. No significant sex differences in toy choices were found following the nonstereotyped introductions. Following the stereotyped introductions, the children's toy choices were consistent with sex-role stereotypes. These results are consistent with laboratory studies suggesting that bias in the introduction of toys by adults may contribute to the sex-typing of specific activities.     

Toddlers’ social evaluations of agents who act on false beliefs

Mature social evaluations privilege agents’ intentions over the outcomes of their actions, but young children often privilege outcomes over intentions in verbal tasks probing their social evaluations. In three experiments (N = 118), we probed the development of intention-based social evaluation and mental state reasoning using nonverbal methods with 15-month-old toddlers. Toddlers viewed scenarios depicting a protagonist who sought to obtain one of two toys, each inside a different box, as two other agents observed. Then, the boxes’ contents were switched in the absence of the protagonist and either in the presence or the absence of the other agents. When the protagonist returned, one agent opened the box containing the protagonist's desired toy (a positive outcome), and the other opened the other box (a neutral outcome). When both agents had observed the toys move to their current locations, the toddlers preferred the agent who opened the box containing the desired toy. In contrast, when the agents had not seen the toys move and therefore should have expected the desired toy's location to be unchanged, the toddlers preferred the agent who opened the box that no longer contained the desired toy. Thus, the toddlers preferred the agent who intended to make the protagonist's desired toy accessible, even when its action, guided by a false belief concerning that toy's location, did not produce a positive outcome. Well before children connect beliefs to social behavior in verbal tasks, toddlers engage in intention-based evaluations of social agents with false beliefs.     

自闭症谱系障碍社交动机理论：机制及干预探索

自闭症谱系障碍(Autism Spectrum Disorder, ASD)表现为社会交往困难以及重复刻板兴趣或行为。社交动机理论提出ASD个体是由于社交动机缺乏导致的社交障碍。目前该理论缺乏理论元素及结构关系的系统论证, 及基于此理论的低龄ASD儿童群体的研究证据。本研究拟采用心理实验法、眼动及近红外脑成像技术, 探索低龄ASD儿童早期社交奖赏、社交定向异常眼动标记及眶额叶脑区活动的神经机制。此外, 通过音乐奖赏强化学习的干预方式改善该理论的核心元素(社交奖赏), 观测能否改善ASD儿童的社交动机。本研究的开展有望对该理论进行系统验证, 并形成改善社交行为的潜在干预方案。     

Preschool Children's Understanding of Conflicting Desires

This study examines the conditions under which 3-year-olds can use the desires of others to predict others' behavior. In Study 1, children were highly successful in predicting the actions of an agent based on that agent's desires when they were explicitly told about the agent's desires, even when the agent's desires were strongly different from the children's own. Study 2 showed that 3-year-olds could also predict the actions of an agent when they had to infer the agent's desires from the previous good and bad experiences of the agent and from information about the agent's general behavioral preferences. Studies 3 and 4 demonstrated that children had difficulty predicting an agent's behavior when they both had to infer the desire of the agent and this desire conflicted with their own desires. These results suggest that preschoolers' desire reasoning is sophisticated but also may be influenced by the processing demands of the task.     

Predictors of Gender-Typed Toy Purchases by Prospective Parents and Mothers: The Roles of Childhood Experiences and Gender Attitudes

Gender differences in children’s toy interests are among the largest in the psychological literature. Parents are often the primary purchasers of children’s toys. In these studies, we investigated the factors that predict whether parents and prospective parents will purchase gender-typed toys for their children or future children. Prospective parents (Study 1, n?=?238, 151 women, 87 men) and mothers (Study 2, n?=?96) reported their retrospective childhood interests, likelihood of purchasing gender-typed toys, stereotypes about toys, and environmental versus essentialist attributions for perceived gender differences in children’s toys. Across both studies, participants reported playing with gender-typed toys more than cross-gender toys as children. They also planned to purchase gender-typed toys for their prospective children (Study 1) or their own children (Study 2). Participants endorsed more stereotypes for feminine toys than for masculine toys and indicated that they believe that gender differences in children’s interests are mostly environmentally influenced, with some biological influence. In addition, gender-typed toy interests as a child predicted the likelihood of purchasing gender-typed toys for their own children. Among women, having nontraditional interests as a child predicted the likelihood they would purchase nontraditional toys for their own children. This relationship was mediated by the endorsement of gender stereotypes among prospective parents (Study 1), but not among mothers (Study 2).     

The police officer's dilemma: using ethnicity to disambiguate potentially threatening individuals

Using a simple videogame, the effect of ethnicity on shoot/don't shoot decisions was examined. African American or White targets, holding guns or other objects, appeared in complex backgrounds. Participants were told to "shoot" armed targets and to "not shoot" unarmed targets. In Study 1, White participants made the correct decision to shoot an armed target more quickly if the target was African American than if he was White, but decided to "not shoot" an unarmed target more quickly if he was White. Study 2 used a shorter time window, forcing this effect into error rates. Study 3 replicated Study 1's effects and showed that the magnitude of bias varied with perceptions of the cultural stereotype and with levels of contact, but not with personal racial prejudice. Study 4 revealed equivalent levels of bias among both African American and White participants in a community sample. Implications and potential underlying mechanisms are discussed.     

Effects of Perceived Consensus on Selective Reinforcement of Other People's Stated Opinions

Three studies tested whether perceived consensus affects selective reinforcement of other people's stated opinions on important social issues. Participants who perceived relatively high consensus for their opinions were more likely than participants who perceived low consensus to reward another person's agreeing statements more than the person's disagreeing statements about gun control (Study 1) and to prolong interrogating another student about abortion (Study 2). In Study 3, participants who were told they were in a two-thirds majority regarding gay scout troop leaders were more likely than participants who were told they were in a one-third minority to practice selective reinforcement. The results have implications for settings in which interrogators believe they can exercise power over the person who is being questioned.     

The role of preschoolers' social understanding in evaluating the informativeness of causal interventions

Preschoolers use information from interventions, namely intentional actions, to make causal inferences. We asked whether children consider some interventions to be more informative than others based on two components of an actor’s knowledge state: whether an actor possesses causal knowledge, and whether an actor is allowed to use their knowledge in a given situation. Three- and four-year-olds saw a novel toy that activated in the presence of certain objects. Two actors, one knowledgeable about the toy and one ignorant, each tried to activate the toy with an object. In Experiment 1, either the actors chose objects or the child chose for them. In Experiment 2, the actors chose objects blindfolded. Objects were always placed on the toy simultaneously, and thus were equally associated with the effect. Preschoolers’ causal inferences favored the knowledgeable actor’s object only when he was allowed to choose it (Experiment 1). Thus, children consider both personal and situational constraints on knowledge when evaluating the informativeness of causal interventions.     

Secure attachment and material reward both attenuate romantic jealousy

Research has shown that social support and materialism can both serve as coping mechanisms, reducing individuals’ experiences of physical and social pain (Zhou and Gao in Psychol Inq 19(3–4):127–144, 2008). We extend this paradigm by testing the buffering effects of secure attachment and material reward on a specific form of social psychological pain: romantic jealousy. Two studies examined the effects of these variables after an imagined relational threat. Participants were primed with (a) secure attachment, (b) material reward, or (c) neutral control, and then responded to a hypothetical scenario involving their romantic partners behaving flirtatiously with a rival. Results from both studies showed that the secure attachment and material reward primes both attenuated jealous responses to the provoking stimuli, relative to the neutral control prime. Neither trait attachment styles nor chronic jealousy moderated the priming effects in Study 1, but attachment styles did slightly moderate the priming effects in Study 2.     

Modeling the effect of reward amount on probability discounting

The present study with college students examined the effect of amount on the discounting of probabilistic monetary rewards. A hyperboloid function accurately described the discounting of hypothetical rewards ranging in amount from $20 to $10,000,000. The degree of discounting increased continuously with amount of probabilistic reward. This effect of amount was not due to changes in the rate parameter of the discounting function, but rather was due to increases in the exponent. These results stand in contrast to those observed with the discounting of delayed monetary rewards, in which the degree of discounting decreases with reward amount due to amount-dependent decreases in the rate parameter. Taken together, this pattern of results suggests that delay and probability discounting reflect different underlying mechanisms. That is, the fact that the exponent in the delay discounting function is independent of amount is consistent with a psychophysical scaling interpretation, whereas the finding that the exponent of the probability-discounting function is amount-dependent is inconsistent with such an interpretation. Instead, the present results are consistent with the idea that the probability-discounting function is itself the product of a value function and a weighting function. This idea was first suggested by Kahneman and Tversky (1979), although their prospect theory does not predict amount effects like those observed. The effect of amount on probability discounting was parsimoniously incorporated into our hyperboloid discounting function by assuming that the exponent was proportional to the amount raised to a power. The amount-dependent exponent of the probability-discounting function may be viewed as reflecting the effect of amount on the weighting of the probability with which the reward will be received.     

Degree of Delay Discounting as a Function of Who Receives the Outcome and the Discounter’s Perceived Level of Social Support

Delay discounting occurs when the subjective value of an outcome decreases as its delivery is delayed. The present study investigated whether how individuals discount delayed outcomes would vary as a function of who would hypothetically experience the outcome and the participants’ perceived level of social support. In Experiment One, 600 university students completed a measure of perceived social support and a discounting task involving four different outcomes, with different groups differing in terms of who would hypothetically receive the outcome being discounted (themselves, their mother, or a classmate). The degree of discounting did not vary as a function of recipient of the outcome, but did vary significantly and inversely with perceived level of social support. Experiment Two replicated the effect of perceived social support in 488 university students, but failed to demonstrate that the degree of discounting varied as a function of the level of social support available to the recipient of the outcome being discounted. These results suggest that people discount outcomes similarly regardless of who will be the recipient of the outcome, but that rates of discounting are reliably altered by the discounter’s own perceived level of social support. The latter finding is potentially informative as to why social-support groups may be valuable in therapeutic environments.