Post-training cyclooxygenase-2 (COX-2) inhibition impairs memory consolidation

Evidence indicates that prostanoids, such as prostaglandins, play a regulatory role in several forms of neural plasticity, including long-term potentiation, a cellular model for certain forms of learning and memory. In these experiments, the significance of the COX isoforms cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) in post-training memory processes was assessed. Adult male Long-Evans rats underwent an eight-trial (30-sec intertrial interval) training session on a hippocampus-dependent (hidden platform) or dorsal striatal–dependent (visible platform) tasks in a water maze. After the completion of training, rats received an intraperitoneal injection of the nonselective COX inhibitor indomethacin, the COX-1–specific inhibitor piroxicam, the COX-2–specific inhibitor N-[2-cyclohexyloxy-4-nitrophenyl]-methanesulfonamide (NS-398), vehicle (45% 2-hydroxypropyl-β-cyclodextrin in distilled water), or saline. On a two-trial retention test session 24 h later, latency to mount the escape platform was used as a measure of memory. In the hidden platform task, the retention test escape latencies of rats administered indomethacin (5 and 10 mg/kg) or NS-398 (2 and 5 mg/kg) were significantly higher than those of vehicle-treated rats, indicating an impairment in retention. Injections of indomethacin or NS-398 that were delayed 2 h post-training had no effect on retention. Post-training indomethacin or NS-398 had no influence on retention of the visible platform version of the water maze at any of the doses administered. Furthermore, selective inhibition of COX-1 via post-training piroxicam administration had no effect on retention of either task. These findings indicate that COX-2 is a required biochemical component mediating the consolidation of hippocampal-dependent memory.     

Neural computation as a tool to differentiate perceptual from emotional processes: The case of anger superiority effect

Research findings in social and cognitive psychology imply that it is easier to detect angry faces than happy faces in a crowd of neutral faces [Hansen, C. H., & Hansen, R. D. (1988). Finding the face in the crowd – An anger superiority effect. Journal of Personality and Social Psychology, 54(6), 917–924]. This phenomenon has been held to have evolved over phylogenetic development because it was adaptive to quickly and accurately detect a potential threat in the environment. However, across recent studies, a controversy has emerged about the underlying perceptual versus emotional factors responsible for this so-called anger superiority effect [Juth, P., Lundqvist, D., Karlsson, A., & Ohman, A. (2005). Looking for foes and friends: Perceptual and emotional factors when finding a face in the crowd. Emotion, 5(4), 379–395; Purcell, D. G., Stewart, A. L., & Skov, R. B. (1996). It takes a confounded face to pop out of a crowd. Perception, 25(9), 1091–1108]. To tease apart emotional and perceptual processes, we used neural network analyzes of human faces in two different simulations. Results show that a perceptual bias is probably acting against faster and more accurate identification of anger faces compared to happy faces at a purely perceptual level. We suggest that a parsimonious hypothesis related to the simple perceptual properties of the stimuli might explain these behavioral results without reference to evolutionary processes. We discuss the importance of statistical or connectionist analysis for empirical studies that seek to isolate perceptual from emotional factors, but also learned vs. innate factors in the processing of facial expression of emotion.     

Sound level of background music and alcohol consumption: an empirical evaluation

The effect of background music on alcohol consumption has been widely researched in the literature, but few studies have tested the effect of sound level on drinking behavior. An experiment was carried out in two bars to test patrons' response to music's loudness. Using random assignment, patrons were exposed to a sound level which was higher than that usually employed in the bars in which the study took place. Analysis showed that a higher sound level than usual was associated with consuming more drinks. An "arousal" hypothesis is used to explain the findings.     

Training synaesthesia

Synaesthetic inducers such as graphemes are typically cultural artifacts. Thus, a learning component seems evident in synaesthesia (Simner et al, 2009 Brain 132 57-64). Normally, synaesthetes report to have their experiences since they can remember. Nevertheless, a recent training study suggests that synaesthesia can be mimicked in non-synaesthetes. To date, the role of learning during the development of synaesthesia is still debated. It is not clear whether synaesthesia can be learned or trained at all. To address this question, we compared a non-adaptive and an adaptive training for their effectiveness. We assessed their impact on two types of priming tasks, before and after the training. We found stronger priming in the adaptive training group suggesting that adaptive training is more efficient to mimic synaesthesia.     

A methodological note on nonlinear time series analysis: is the open- and closed-loop model of Collins and De Luca (1993) a statistical artifact?

The authors reexamined, theoretically and empirically, the method proposed by J. J. Collins and C. D. De Luca (1993) for the analysis of center-of-pressure trajectories. The main argument in this article is that Collins and De Luca's approach is not adapted to the analysis of bounded time series and leads to statistical artifacts such as underestimation of the diffusion process for long-term intervals. The open- and closed-loop model developed by Collins and De Luca is a direct consequence of those statistical problems. Applying more classical methods, such as rescaled range analysis or detrended fluctuation analysis, the authors show that center-of-pressure trajectories can be modeled as continuous, antipersistent fractional Brownian motion. More specifically, those trajectories behave like 1/f noise, a ubiquitous feature in adaptive biological systems.     

“One Doesn’t Slap a Girl but…” Social Representations and Conditional Logics in Legitimization of Intimate Partner Violence

The present research, which fits into the conceptual framework of social representations, aims to analyze the impact of gender and legitimizing ideologies on the evaluation of intimate partner violence (IPV). Using an inductive mixed methods approach, two studies were conducted in a French context. In Study 1, 24 participants were asked to express their views about a vignette describing an IPV case during semi-structured interviews. In Study 2, 123 participants completed a questionnaire which was based on the results of Study 1. They were asked to evaluate the severity and justification for this same IPV case in relation to several situations identified in interviews. They also completed two scales measuring adherence to ideologies legitimizing male dominance: the Ambivalent Sexism Inventory and the Domestic Violence Myth Acceptance Scale. Results show expressed ambivalence by participants between condemnation of IPV and the use of conditional logics in order to minimize or justify it. The expression of this reasoning was determined by social regulations such as the situations in which the violence occurred and adherence to legitimizing ideologies. Our results are relevant for campaigns raising awareness and educational programs that take into account social representations underlying IPV legitimization.     

Early and late cortical responses to directly gazing faces are task dependent

Gender categorisation of human faces is facilitated when gaze is directed toward the observer (i.e., a direct gaze), compared with situations where gaze is averted or the eyes are closed (Macrae, Hood, Milne, Rowe, & Mason, Psychological Science, 13(5), 460–464, 2002). However, the temporal dynamics underlying this phenomenon remain to some extent unknown. Here, we used electroencephalography (EEG) to assess the neural correlates of this effect, focusing on the event-related potential (ERP) components known to be sensitive to gaze perception (i.e., P1, N170, and P3b). We first replicated the seminal findings of Macrae et al. (2002, Experiment 1) regarding facilitated gender discrimination, and subsequently measured the underlying neural responses. Our data revealed an early preferential processing of direct gaze as compared with averted gaze and closed eyes at the P1, which reverberated at the P3b (Experiment 2). Critically, using the same material, we failed to reproduce these effects when gender categorisation was not required (Experiment 3). Taken together, our data confirm that direct gaze enhances the early P1, as well as later cortical responses to face processing, although the effect appears to be task dependent.     

Mimicry and helping behavior: an evaluation of mimicry on explicit helping request

Research found that mimicry behavior led to increased helping behavior toward the mimicker and is associated with higher positive evaluation of the mimicker. Furthermore, studies on helping behavior focused only on implicit helping behavior, whereas no experimental study on explicit helping request was tested. An experiment was carried out in which a female student-confederate mimicked or not mimicked a participant during a discussion about paintings and, after that, solicited the participant for a written feedback about an essay. It was found that mimicry increased compliance to the confederate's request.