The basolateral amygdala is necessary for learning but not relearning extinction of context conditioned fear

Extinction of conditioned fear involves new learning that inhibits but does not eliminate the original fear memory. This inhibitory learning is thought to require activation of NMDA receptors (NMDAr) within the basolateral amygdala (BLA). However, once extinction has been learned, the role played by the BLA during subsequent extinction procedures remains unknown. The present study examined the role of neuronal activity and NMDAr activation in rats receiving their first or second extinction of context fear. We found that BLA infusion of DL-APV, a competitive antagonist of NMDAr, depressed fear responses at both the first and second extinction. It impaired learning extinction but spared and even facilitated relearning extinction. BLA infusion of muscimol, a GABA(A) agonist, produced a similar outcome, suggesting that DL-APV not only blocked NMDAr-dependent plasticity but also disrupted neuronal activity. In contrast, infusion of ifenprodil, a more selective antagonist of NMDAr containing the NR2B subunit, did not depress fear responses but impaired short- and long-term inhibition of fear at both the first and second extinction. Therefore, we suggest that relearning extinction normally requires NMDAr containing the NR2B subunit in the BLA. However, simultaneous blockade of these receptors and neuronal activity in the BLA results in compensatory learning that is able to promote long-term re-extinction. These data are consistent with a current model that attributes fear extinction to interactions between several neural substrates, including the amygdala and the medial prefrontal cortex.     

To whom does voice in groups matter? Effects of voice on affect and procedural fairness judgments as a function of social dominance orientation

The authors investigated the effects of voice--the opportunity to provide input in decision-making processes--on perceptions of procedural fairness. In particular, the authors studied the moderating role of social dominance orientation (SDO) in shaping this relation. SDO is an important individual differences variable that causes people to favor unequal relationships within and between social groups. Results revealed that voice was more strongly related to fairness judgments when participants had a high rather than low SDO. Moreover, positive affect mediated this moderation effect. The authors interpreted these results to indicate that high-SDO participants were especially sensitive to voice manipulations because such manipulations enhance perceptions of control over group resources and outcomes. The authors conclude by discussing alternative explanations based on other fairness theories.     

It all sounds the same to me: Sequential ERP and behavioral effects during pitch and harmonicity judgments

The representation of complex sounds was examined by comparing both behavioral and event-related brain potentials (ERPs) to the change or repetition of fundamental frequency (f0) and harmonicity. In the pitch task, participants were asked to categorize the incoming stimulus as either low or high, regardless of harmonicity, and in the harmonicity task, participants indicated whether the stimulus was tuned or mistuned, regardless of pitch. Over three experiments, participants were faster in responding to pitch than to harmonicity. As a result of this asymmetry, behavioral and ERP data showed that irrelevant changes in harmonicity had little impact on performance during the pitch task, whereas harmonicity judgments were impeded by irrelevant changes in f0. These data are consistent with both general horse-race accounts of processing and specific accounts of mistuning detection that posit prior f0 registration. In addition, ERP components N2 and P3 were modulated by both intertrial contingency and task instructions, revealing the further influence of top-down mechanisms on concurrent sound segregation.     

Does materialism predict racism? materialism as a distinctive social attitude and a predictor of prejudice

Previous research reported that Right‐Wing Authoritarianism (RWA) and Social Dominance Orientation (SDO) constitute the individual's ideological space and are strong dispositional determinants of racism. In the present study, materialism was examined as a third social attitude and a potential predictor of racism. In a student (N = 183) and heterogeneous adult sample (N = 176) analyses revealed that RWA, SDO and materialism constitute three separate dimensions and that each of them explains a unique part of the variance in racism. In addition, Structural Equation Modelling showed that the relationship between materialism and racism was largely mediated by selfish motives. In the discussion we go further into the role of materialism as a third social attitudinal dimension. Copyright © 2006 John Wiley & Sons, Ltd.     

Effect of a short nap on the alertness of young drivers: Repercussion on the perception of motorcycles according to extent of the useful visual field of the driver

The objectives of this study are to analyze the effect of a short nap on the level of alertness and on the drivers’ ability to detect the motorcyclists on the road according to the size of his/her useful visual field (UVF).Nineteen participants (m = 21 years old) carried out a driving task with a simulator, after taking a short nap (30 min) in the vehicle or not. They had to distinguish the colour change of a signal on a vehicle they were following and to detect a motorcycle which briefly appeared on the road at different eccentricities.Drivers with a limited UVF are those who detect the fewest motorcycles. Taking a short nap before the driving does not have any significant effect on data related to vision (motorcycles and signals detected), driving and alertness state ((α+θ)/β). There is a linear relationship between the size of the UVF and the ability to detect the motorcycle appearing in the left outside mirror.The implications of the results concerning the short nap as a countermeasure to a decrease in alertness and the perception of motorcycles according to extent of the useful visual field of the driver are discussed in terms of road safety.     

Performance-approach and performance-avoidance goals: when uncertainty makes a difference

Performance-avoidance goals (the desire to avoid performing more poorly than others do) have been shown to have consistently deleterious effects on performance but the effects of performance-approach goals (trying to outperform others) are more complex. Two studies examine uncertainty as a moderator of the effect of performance-approach goals on performance. Experiment 1 shows that manipulated performance-approach goals lead to better performance than do performance-avoidance goals in the absence of uncertainty about performance but when participants learn that a coactor disagreed with them about problem solutions, creating uncertainty, performance-approach goals do not differ from performance-avoidance goals in their effect on performance. Experiment 2 shows that uncertainty also moderates the effects of self-set performance-approach goals. Moreover, the same dynamic occurs with another kind of uncertainty: negative competence feedback.     

Separating ability from need: clarifying the dimensional structure of the Need for Closure Scale

The validity of the Need for Closure Scale (NFCS) has recently been debated in the research literature. In the present study, it is argued that the traditional Decisiveness scale primarily taps ability content instead of the hypothesized motivational need; therefore, new items that explicitly probe the need for quick and unambiguous answers were developed. It was shown that these need items form a reliable scale (Study 1); were predictive of the seizing process over and beyond ability, whereas the old Decisiveness scale was not (Study 2); and were sensitive to experimentally manipulated levels of task motivation (Study 3). Finally, a reassembled NFCS with the new items replacing the traditional Decisiveness items showed superior fit as a unidimensional model. In the Discussion, it is argued that the specific position of Decisiveness is due to its particular operationalization, not to its theoretical status.     

Spatial navigation: Cognitive variables involved in route retracing among an elderly population

The cognitive processes involved in route retracing are not well known. This study aims to highlight them in an elderly population in which contradictory results have been obtained, certain studies showing specific difficulties for route retracing, others not. Thirty-nine elderly subjects performed a route-learning task (forward-backward) in a garden, then completed spatial knowledge tasks and standardised cognitive tests. Results show four factors that were predictive of route retracing performance: route repetition, the pointing task, and two standardised cognitive tests, one assessing spatial working memory, and another global cognitive efficiency. According to these results, route retracing involves route and survey knowledge (i.e., egocentric and allocentric strategy), and the integration of forward-backward perspectives is underpinned by the spatial working memory. Moreover, the subjects did not make more errors in route retracing than in the route repetition task, suggesting that a real environment could compensate for a failing allocentric strategy.