Economic principles motivating social attention in humans. (41/310)

We know little about the processes by which we evaluate the opportunity to look at another person. We propose that behavioural economics provides a powerful approach to understanding this basic aspect of social attention. We hypothesized that the decision process culminating in attention to another person follows the same economic principles that govern choices about rewards such as food, drinks and money. Specifically, such rewards are discounted as a function of time, are tradable for other rewards, and reinforce work. Behavioural and neurobiological evidence suggests that looking at other people can also be described as rewarding, but to what extent these economic principles apply to social orienting remains unknown. Here, we show that the opportunity to view pictures of the opposite sex is discounted by delay to viewing, substitutes for money and reinforces work. The reward value of photos of the opposite sex varied with physical attractiveness and was greater in men, suggesting differential utility of acquiring visual information about the opposite sex in men and women. Together, these results demonstrate that choosing whom to look at follows a general set of economic principles, implicating shared neural mechanisms in both social and non-social decision making.  (+info)

Social transmission of disinhibition in young children. (42/310)

The present study examined whether young children's behaviors in the Dimensional Change Card Sorting task can be influenced by their observation of another person performing the task. Experiment 1 showed that after children watched an adult sorting cards according to one rule, although the children were instructed to sort the cards according to a new rule, most 3-year-olds made perseverative errors and used the observed, old rule to sort the cards instead of the new rule. However, only some 4-year-olds and few 5-year-olds made the same mistake. Experiments 2, 3 and 4 showed that the younger children took into consideration social pragmatic information displayed by the adult model when deciding to use the old rule or the new rule. When the model appeared to know that she sorted the cards incorrectly (Experiments 2 and 3), or was uncertain whether she sorted cards correctly (Experiment 4), most 3-year-olds no longer committed perseverative errors. When the adult model was confident about her sorting or oblivious to her sorting errors, most 3-year-olds made perseverative errors. These results taken together suggest that social observation can lead to disinhibitions. In other words, disinhibition can be transmitted socially from one person to another.  (+info)

Neural responses to taxation and voluntary giving reveal motives for charitable donations. (43/310)

Civil societies function because people pay taxes and make charitable contributions to provide public goods. One possible motive for charitable contributions, called "pure altruism," is satisfied by increases in the public good no matter the source or intent. Another possible motive, "warm glow," is only fulfilled by an individual's own voluntary donations. Consistent with pure altruism, we find that even mandatory, tax-like transfers to a charity elicit neural activity in areas linked to reward processing. Moreover, neural responses to the charity's financial gains predict voluntary giving. However, consistent with warm glow, neural activity further increases when people make transfers voluntarily. Both pure altruism and warm-glow motives appear to determine the hedonic consequences of financial transfers to the public good.  (+info)

Via freedom to coercion: the emergence of costly punishment. (44/310)

In human societies, cooperative behavior in joint enterprises is often enforced through institutions that impose sanctions on defectors. Many experiments on so-called public goods games have shown that in the absence of such institutions, individuals are willing to punish defectors, even at a cost to themselves. Theoretical models confirm that social norms prescribing the punishment of uncooperative behavior are stable-once established, they prevent dissident minorities from spreading. But how can such costly punishing behavior gain a foothold in the population? A surprisingly simple model shows that if individuals have the option to stand aside and abstain from the joint endeavor, this paves the way for the emergence and establishment of cooperative behavior based on the punishment of defectors. Paradoxically, the freedom to withdraw from the common enterprise leads to enforcement of social norms. Joint enterprises that are compulsory rather than voluntary are less likely to lead to cooperation.  (+info)

Individual differences in reward responding explain placebo-induced expectations and effects. (45/310)

Expectations, positive or negative, are modulating factors influencing behavior. They are also thought to underlie placebo effects, impacting perceptions and biological processes. Using healthy human subjects, we examined the role of the nucleus accumbens (NAC), a region centrally involved in the encoding of reward expectation, in the formation of placebo responses. Employing functional molecular imaging, activation of NAC dopamine (DA) release was observed during placebo administration and related to its anticipated effects, perception-anticipation mismatches, and placebo effect development. In additional functional MRI studies, the expectation of monetary gain increased NAC synaptic activity in a manner proportional to placebo-induced DA release, anticipated effects, perception-anticipation differentials, and actual placebo effects. Individual variations in NAC response to reward expectation accounted for 28% of the variance in the formation of placebo analgesia.  (+info)

A bingo game motivates students to interact with course material. (46/310)

OBJECTIVES: To create a bingo game that would increase student interaction with course material and provide students with options for demonstrating learning and earning extra credit. DESIGN: A bingo game was created in which each of the 25 squares contained an activity (eg, video, crossword puzzle, poem, quiz) that encouraged interaction with course material and appealed to multiple learning styles. Students who achieved bingo earned a 5-point (5%) grade bonus. ASSESSMENT: All students enrolled in the Introduction to Clinical Pharmacy Skills course participated in the bingo game. The majority of students (74.6% in the fall and 81.9% in the spring) achieved bingo. Students who achieved bingo had an average course grade 7 points (fall semester) and 10 points (spring semester) higher than the average course grade from the prior 6 semesters. CONCLUSION: The bingo game increased student interaction with course material throughout the semester and provided students with options for demonstrating learning.  (+info)

Chimpanzees are rational maximizers in an ultimatum game. (47/310)

Traditional models of economic decision-making assume that people are self-interested rational maximizers. Empirical research has demonstrated, however, that people will take into account the interests of others and are sensitive to norms of cooperation and fairness. In one of the most robust tests of this finding, the ultimatum game, individuals will reject a proposed division of a monetary windfall, at a cost to themselves, if they perceive it as unfair. Here we show that in an ultimatum game, humans' closest living relatives, chimpanzees (Pan troglodytes), are rational maximizers and are not sensitive to fairness. These results support the hypothesis that other-regarding preferences and aversion to inequitable outcomes, which play key roles in human social organization, distinguish us from our closest living relatives.  (+info)

Ventral frontal cortex functions and quantified MRI in traumatic brain injury. (48/310)

Ventral frontal cortex is commonly involved in traumatic brain injury (TBI). The smell identification test (SIT), object alternation (OA), and the Iowa gambling task (IGT) are associated with this brain region in experimental and neuropsychological research. We examined the relationship of performance on these tests to residual structural brain integrity quantified from MRI in 58 TBI patients, including 18 patients with focal cortical contusions and 40 patients with diffuse injury only. Image analysis yielded regional volumetric measures of gray matter, white matter and cerebrospinal fluid. Multivariate analyses identified distributed patterns of regional volume loss associated with test performance across all three behavioral measures. The tasks were sensitive to effects of TBI. In multivariate analyses, performance in all three tasks was related to gray matter loss including ventral frontal cortex, but the SIT was most sensitive to ventral frontal cortex damage, even in patients without focal lesions. The SIT was further related to temporal lobe and posterior cingulate/retrosplenial volumes. OA and the IGT were associated with superior medial frontal volumes. Complex tasks, such as OA and the IGT, do not consistently localize to a single cortical region. The SIT is associated with the integrity of ventral frontal regions, but it is also affected by distributed damage, although the contribution of undetected olfactory tract or bulb damage could not be ruled out. This study illustrates the scope and limitations of functional localization in human ventral frontal cortex.  (+info)