Doping dependence of the Nernst effect in Eu(Fe1-xCox)2As2 - departure from Dirac fermions physics

We report a systematic study of the transport properties in the series of Eu(Fe1-xCox)2As2 single crystals with x = 0, 0.15, 0.20 and 0.30. Spin-density-wave order is observed in the undoped and the least doped samples (x = 0, 0.15), while for x = 0.15 and 0.20 Eu(Fe1-xCox)2As2 becomes a superconductor. We found the properties of the parent EuFe2As2 compound well described by the Dirac fermions model, whereas cobalt doping caused an evolution of the system toward a regular metallic state. The antiferromagnetic ordering of the Eu2+ ions at T_N ~ 20 K has only minor influence on the measured quantities.Comment: 5 pages, 5 figures; ver.3: the sign convention for the Nernst coefficient is change

The impact of incidental fear and anger on in- and outgroup attitudes

The aim of this research was to examine the impact of two specific negative emotions of anger and fear on intergroup attitudes. In Study 1 we measured emotions of anger and fear and in Study 2 we evoked these emotions incidentally, that is independently of any intergroup context. In both studies we measured attitudes towards the ingroup (Polish) and the outgroup (Gypsies).We expected that fear would lead to more positive ingroup attitudes and anger to more negative outgroup attitudes. The results of the correlational study (Study 1) confirmed the predictions regarding anger and decreased outgroup evaluations, and the experimental study (Study 2) revealed that fear enhanced positivity towards the ingroup, but anger increased negativity towards the outgroup. The impact of fear and anger on social attitudes in the specific context of a negatively self-stereotyped ingroup is discussed

When need for closure leads to positive attitudes towards a negatively stereotyped outgroup

The study examined the relationship between epistemic motivation, which is the need for closure (NFC), and positive attitudes towards a negatively stereotyped outgroup (i.e., Gypsies). Although extensive research has revealed that NFC is related to derogatory behavioural tendencies and negative emotions towards stereotyped groups, it is proposed that NFC may also be linked to positive attitudes towards outgroups. It is predicted, however, that this would be true only when NFC is accompanied by a low ability to achieve closure (AAC). It is argued that low AAC impairs the construction of schema and their effective application. Therefore, NFC in individuals with low AAC may lead them to correct their initial tendency to use stereotypes and, as a consequence, to evaluate a negatively stereotyped outgroup in a positive way. In this research, low AAC was assessed by a scale (Study 1) and experimentally induced (Study 2). In both studies, we measured positive attitudes towards Gypsies. The results of the studies supported our prediction that NFC is positively related to positive attitudes towards Gypsies when AAC is low

Two routes to closure : time pressure and goal activation effects on executive control

In the present study the impact of need for cognitive closure (NFC) manipulations via time pressure and explicit closure goal activation on executive control was investigated. Although there is some evidence that NFC, measured as an individual variable, is related to better performing in attentional tasks involving executive control, these results have never been validated across different manipulations of NFC. Thus, in the present study we induced NFC via internal and external time pressure and tested the impact of these manipulations on the performance in tasks that measure executive control, i.e., the Stroop and switching tasks. The results revealed that induced high (vs. low) NFC, indeed boosted performance in executive control tasks. Moreover, there was no difference in the effect of both NFC manipulations on task performance. The implications regarding the role of executive control and specific NFC manipulations in social cognition are discussed

The child as an observer : the influence of adults’ nonverbal messages on children’s social attitudes

Previous research showed that children can exhibit preferences for social categories already at preschool age. One of the crucial factors in the development of children’s attitudes toward others is children’s observation and imitation of adults’ nonverbal messages. The aim of our study is to examine whether children’s tendency to perceive and follow nonverbally expressed attitudes toward other people is related to ingroup bias, i.e. the tendency to favor one’s own group over other groups. We examined 175 preschool children (age in months: 61-87; M = 72.6, SD = 6.53) presenting them with a video of a conversation between a message sender and a message recipient. The study was conducted in a minimal group paradigm. We found that children accurately identified the message sender’s attitude toward the recipient and also generalized this attitude to other members of the new group. We also found explicit ingroup bias among children from the message sender’s group. However, no generalization of the sender’s attitude to other ingroup members was found. The results are discussed in reference to previous findings on the role of imitation of adult’s non-verbal behavior for the development of social attitudes among children

The impact of background category information on the creation of social cliques: the role of need for cognitive closure and decisiveness

This article focuses on the role of need for cognitive closure in the process of mental model creation about social relations (i.e. social cliques). We assumed that high (vs. low) need for closure participants tend to rely on background category information when forming social cliques. We predicted that this tendency to employ categorical information as a mental aid, used in order to form social cliques, would be efficient in simple task structures (where category information overlaps with the mental model structure) but would lead to increased error rates in complex task structures (where category information is inconsistent with the model structure). The results confirmed our predictions, showing especially strong effects for the decisiveness component of need for closure. The importance of individual differences in need for closure and decisiveness in social reasoning is discussed

Limits of control : the effects of uncontrollability experiences on the efficiency of attentional control

Two experiments were conducted to explore the effects of experiencing uncontrollability on the efficiency of attentional control. The experience of uncontrollability was induced either by unsolvable tasks (Experiment 1) or by tasks in which non-contingent feedback was provided (Experiment 2). A version of the Attentional Network Test-Interactions with an additional measure of vigilance (ANTI-V) was used to evaluate the efficiency of the attentional networks (i.e., alerting, orienting, and executive). Results of both experiments revealed a decreased efficiency of executive attention in participants who experienced stable control deprivation but no negative effects in participants who were able to restore their sense of previously deprived control. Additionally, when participants were asked to perform unsolvable tasks and did not receive feedback (Experiment 1), detrimental effects on the orienting network and vigilance were observed. The motivational and cognitive mechanisms underlying the effects of various uncontrollability experiences on conflict resolution and attentional control are discussed

Fast or accurate? : the change of goals modulates the efficiency of executive control

In the present study, we analyse the influence of goal maintenance and goal change on the efficiency of executive control. Although there is empirical evidence on the impact of goal maintenance and task-switching on executive control, little is known about the consequences of changing between processing goals (e.g., speed or accuracy goals). We assessed the influence of changing between speed and accuracy goals while performing a task-switching procedure that requires social categorization. Experiment 1 included frequent goal changes, whereas Experiment 2 included one goal change across the experimental session. The results showed that both goals influence general performance and flexibility. A comparison between experiments suggested that frequent goal change (Experiment 1) resulted in worse performance and lower flexibility overall, compared to sequential goal change (Experiment 2). Frequent goal change was also associated with increased difficulties in pursuing the accuracy goal. The implications regarding the role of goal maintenance and goal change on executive control are discussed, as well as new research possibilities

Self-image threat decreases stereotyping : the role of motivation toward closure

Some prior research indicated that self-image threat may lead people to stereotyping and prejudiced evaluations of others. Other studies found that self-image threat may promote less stereotypical thinking and unprejudiced behavior. In a series of three studies, we demonstrate that self-image threat may lead to either more or less stereotypical perception of the outgroup depending on the level of the individuals` motivation toward closure (NFC). The results reveal that when individuals high (vs. low) in NFC perceived a member of an outgroup, they are less likely to use stereotypical traits if their self-image had been threatened by negative feedback (Study 1) or if they had imagined an example of their own immoral activity (Studies 2 and 3). Moreover, our results demonstrate that the fear of invalidity resulting from self-image threat induction is responsible for the foregoing effects (Study 3). These results are discussed in light of theories of motivational readiness and lay epistemics