Witnessing postevents does not change memory traces,but can affect their retrieval

The results of three experiments suggest that a memory trace for an event is not altered by witnessing similar events, but that postevents can interfere with its retrieval. On an immediate recall test, details from an original story (e.g. wrench) were recalled less often if a subsequent story mentioned a ‘screwdriver’ than if it did not. The interference effect occurred if people were asked to recall details fromboth stories (tool —— ——), but not if people were asked to recall primarily from the first story. Thus, the interference effect in immediate recall was averted if the target trace could be activated selectively (Experiments 1a and 1b). A more general interference effect was found after a day. Fewer targets from the original story were recalled if the second story was presented just before the test than if both stories occurred a day earlier. Thus, the second story interfered with recall only if it emphasized contextual retrieval cues that did not match the trace for the targets (Experiment 2). Copyright © 2001 John Wiley & Sons, Ltd.     

Mechanical knowledge does matter to tool use even when assessed with a non-production task: Evidence from left brain-damaged patients

In the literature on apraxia of tool use, it is now accepted that using familiar tools requires semantic and mechanical knowledge. However, mechanical knowledge is nearly always assessed with production tasks, so one may assume that mechanical knowledge and familiar tool use are associated only because of their common motor mechanisms. This notion may be challenged by demonstrating that familiar tool use depends on an alternative tool selection task assessing mechanical knowledge, where alternative uses of tools are assumed according to their physical properties but where actual use of tools is not needed. We tested 21 left brain-damaged patients and 21 matched controls with familiar tool use tasks (pantomime and single tool use), semantic tasks and an alternative tool selection task. The alternative tool selection task accounted for a large amount of variance in the single tool use task and was the best predictor among all the semantic tasks. Concerning the pantomime of tool use task, group and individual results suggested that the integrity of the semantic system and preserved mechanical knowledge are neither necessary nor sufficient to produce pantomimes. These results corroborate the idea that mechanical knowledge is essential when we use tools, even when tasks assessing mechanical knowledge do not require the production of any motor action. Our results also confirm the value of pantomime of tool use, which can be considered as a complex activity involving several cognitive abilities (e.g., communicative skills) rather than the activation of gesture engrams.     

Sex differences in relational and overt aggression in the late elementary school years

Sex differences in relational and overt aggression among 3rd (n=176), 4th (n=179), and 5th graders (n=145) from three public schools (n=500; 278 girls) were examined. Nominations of relational aggression increased over time among 4th and 5th grade girls, but not among boys or 3rd grade girls. Among 3rd graders, boys received more nominations for relational aggression than girls. By the end of the 5th grade, girls received more relational aggression nominations than boys. There was also a significant rise in nominations of overt aggression among 5th grade girls, but not among 5th grade boys or younger boys and girls. As expected, boys were more likely than girls to be nominated for overt aggression at all grade levels. The findings are helpful for explaining inconsistencies of earlier research pertaining to sex differences in relational aggression and for advancing our understanding of the causes of aggression. Aggr. Behav. 36:282–291, 2010. © 2010 Wiley‐Liss, Inc.     

Symmetry perception in the blind

Bilateral mirror symmetry, especially vertical symmetry, is a powerful phenomenon in spatial organization of visual shapes. However, the causes of vertical symmetry salience in visual perception are not completely clear. Here we investigated whether the perceptual salience of vertical symmetry depends on visual experience by testing a group of congenitally blind individuals in a memory task in which either horizontal or vertical symmetry was used as an incidental feature. Both blind and sighted subjects remembered more accurately configurations that were symmetrical compared to those that were not. Critically, whereas sighted subjects displayed a higher level of facilitation by vertical than horizontal symmetry, no such difference was found in the blind. This suggests that the perceptual salience of the vertical dimension is visually based.     

Reactive aggression in psychopathy and the role of frustration: Susceptibility,experience, and control

This article is a commentary on ‘Psychopathy, frustration, and reactive aggression: The role of ventromedial prefrontal cortex’ ( Blair, 2010 ).     

Preliminary analysis of the psychometric properties of Ryff's scales of psychological well-being in Portuguese adolescents

This article presents a set of research studies that aim to adapt Carol Ryff's scales of psychological wellbeing (SPWB) and to analyze its psychometric properties in adolescents. The first two studies focused on the reliability and factorial validity of different Portuguese short versions of SPWB, revealing measurement models inadequacies and low internal consistency. In the third study we developed a shortened version (30 items), taking into account the application of psychometric criteria suggested by van Dierendonck (2005). The scales of this version revealed better reliability and adequate goodness of fit indices for the six-factor model, as proposed by Carol Ryff's PWB theory. Although further research focused on the psychometrical properties reanalysis of this shortened version of SPWB is needed, this article provides a contribution to the research and intervention on positive mental health during adolescence.     

Crossmodal interaction between the mental number line and peripersonal haptic space representation in sighted and blind individuals

Humans tend to represent numbers in the form of a mental number line. Here we show that the mental number line can modulate the representation of peripersonal haptic space in a crossmodal fashion and that this interaction is not visually mediated. Sighted and early-blind participants were asked to haptically explore rods of different lengths and to indicate midpoints of those rods. During each trial, either a small (2) or a large (8) number was presented in the auditory modality. When no numbers were presented, participants tended to bisect the rods to the left of the actual midpoint, consistent with the notion of pseudoneglect. In both groups, this bias was significantly increased by the presentation of a small number and was significantly reduced by the presentation of a large number. Hence, spatial shifts of attention induced by number processing are not limited to visual space or embodied responses but extend to haptic peripersonal space and occur crossmodally without requiring the activation of a visuospatial representation.     

Language and executive functioning skills of students with attention deficit/hyperactivity disorder (ADHD), and in reading comprehension difficulties (RCD)

The aim of this work was to study the specificity of deficits in linguistic and executive functioning of students with ADHD and with RCD and to determine the profile of deficits in the comorbid group (ADHD+RCD). Participants in the study were 84 students, ages 12-16 years divided into four groups with an equal number of subjects (N= 21): ADHD, RCD, ADHD+RCD and comparison group (without ADHD and without RCD). We measured vocabulary, oral comprehension, lexical access, verbal and visual working memory, inhibition and attention. The results show that the ADHD+RCD group presents the most important linguistic deficits, followed by the RCD group. On the other hand, the three clinical groups (ADHD, RCD and ADHD+RCD) display greater performance problems in working memory than the comparison group, whereas the two groups with ADHD had more problems in attention and inhibition. These results suggest the dissociation of linguistic and executive deficits that affect the RCD group and ADHD group to a greater extent, respectively. Lastly, the comorbid group showed deficits both in language and in executive skills. We discuss the implications of these findings for designing interventions.