Hand Grip and Load Force Coordination of the Ipsilesional Hand of Chronic Stroke Individuals

Object manipulation depends on a refined control of grip force (GF) and load force (LF). After a brain injury, the GF control is altered in the paretic hand but what happens with the non-paretic hand is still unclear. In this study, we compared the GF control and GF–LF coordination of the non-paretic hand of 10 stroke individuals who suffered right brain damage (RBD) and 10 who suffered left brain damage (LBD), with 20 healthy individuals during lifting and oscillation task, using an instrumented object. GF was recorded with a force transducer, and LF was estimated from the object weight and acceleration. Overall, the ipsilesional hand of stroke individuals, independent of the lesion side, presented similar GF control and GF–LF coordination. However, LBD individuals took longer to start lifting the object, which may be due to the need of more time to obtain somatosensory information from the contact with the object. The findings indicate that stroke individuals preserve their ability to control and coordinate GF and LF when using their ipsilesional hand for object manipulation and the left hemisphere may play an essential role in the processing of somatosensory information needed for the GF control.     

Polyaminergic agents modulate contextual fear extinction in rats

Polyamines, such as spermidine and spermine, have been reported to improve memory retention through the activation of N-methyl-d-aspartate receptors (NMDAr). However whether polyamine agonists and antagonists alter extinction remains unclear. In the current study, we investigated whether spermidine and polyamine antagonists that selectively block the NR2B subunit at the NMDAr alter the extinction of contextual conditioned fear in male Wistar rats. The bilateral intra-hippocampal administration of exogenous spermidine (2 nmol/site) immediately after, but not 6 h after extinction training, facilitated the extinction of fear conditioning. The injection of the NMDAr antagonists arcaine (0.2 nmol/site), ifenprodil (20 nmol/site) and traxoprodil (0.2 nmol/site), disrupted fear extinction and, at doses that had no effect per se, reversed the facilitatory effect of spermidine on fear extinction. These results suggest that exogenous and endogenous polyamines facilitate the extinction of contextual conditioned fear through activation of NR2B subunit-containing NMDAr in the hippocampus. Since extinction-based exposure therapy is widely used as treatment for a number of anxiety-related disorders, including phobias and post-traumatic stress, the currently reported facilitation of extinction by polyaminergic agents suggest these compounds as putative candidates for drug development.     

Problems in the timing of conscious experience

Libet's (2000) arguments in defense of his interpretation of his experimental results are insufficient. The claims of my critical review (Gomes, 1998) do not suffer with his new statements.     

Experimental field study of hand preference in wild black-horned (<Emphasis Type="Italic">Cebus nigritus</Emphasis>) and white-faced (<Emphasis Type="Italic">Cebus capucinus</Emphasis>) capuchins: evidence for individual and species differences

In this experimental field investigation, we compare the degree to which wild capuchins in Brazil (Cebus nigritus) and Costa Rica (Cebus capucinus) exhibit individual- and population-level handedness during three visually-guided tasks. These tasks required reaching to remove a large leaf covering a hidden food reward, seizing the food reward, and manipulating a tool (pulling a wooden dowel) in order to obtain access to an embedded food reward. Studies in some populations of captive capuchins indicate evidence for both individual hand preferences and population-level handedness. In this study, six of eight wild C. capucinus and six of seven wild C. nigritus exhibited a significant hand preference during individual tasks, but no individual exhibited a consistent preference across all three tasks. Task-specialization, or the tendency for most individuals in the same group or population to use the same hand to accomplish a particular task, also was evaluated. Cebus nigritus showed a significant bias toward the use of the right hand in removing the leaf. Although the number of individual capuchins in both species that manipulated the dowels was limited (N = 7), each individual that manipulated the dowels in eight or more instances had a positive handedness index, suggesting a greater use of the right hand to accomplish this task. Overall, our results provide preliminary support for individual- and population-level handedness in wild capuchin monkeys.     

Impulsivity Mediates the Relationship between Future Orientation and Juvenile Deviancy

Both future orientation and impulsivity are intrinsic parts of an adolescent’s self-control, and empirical evidence clearly establishes them as crucial features on the origin of juvenile deviant behavior. However, we do not yet fully understand how these variables relate in explaining deviant conduct. In the present study, we tested a mediation model between these variables among 126 Portuguese adolescents. Findings support the mediation model in analysis, namely that impulsivity fully mediates the effect of future orientation on deviant behavior. In conclusion, our results suggest that lesser future orientated youth develop impulsive behavior which, in turn, explains their higher deviant conduct.     

The interpretation of Libet's results on the timing of conscious events: a commentary

A commentary on articles by Klein, Pockett, and Trevena and Miller, in this issue, is given. Average shift in the point of subjective equality (PSE), calculated by Klein on Libet's data, and corresponding change in mean shift, calculated by Libet et al. (1983), may be "corrected," taking as a reference point the end of the minimum train duration. Values obtained, if significant, indicate a latency for conscious sensation of the skin stimulus of at least 230 ms. Pockett's main conclusions are favored, but her explanation of peripheral-lemniscal couplings is found to be unconvincing. Trevena and Miller's article unsuccessfully tries to rescue a dualist interactionist view. Libet's method of timing intentions is thoroughly criticized.     

Self-reported delinquency among Alberta's youth: findings from a survey of 2,001 junior and senior high school students

This article draws on data from a 1999 survey on youth victimization, crime and delinquency in Alberta conducted by the Canadian Research Institute for Law and the Family in collaboration with researchers from the University of Alberta. The survey included 2,001 youth attending Grades 7 to 12 in public and Catholic schools in selected urban and rural areas in the province. Analyses focus on self-reported past-year delinquency. Statistically significant results were found for relationships between extent of delinquency and gender, grade level, psychosocial problems (as measured by conduct, hyperactivity, and emotional problems), and extent of past-year victimization. For low/moderate delinquency, females were comparable to males, and even reported slightly higher rates for low/moderate violence-related delinquency. Younger students were more likely to indicate engaging in violence-related delinquency, while older students were more likely to report property-related delinquent acts. Overall, Grade 9 students had the highest rates of delinquency. For personal characteristics, a high score on conduct problems was most strongly correlated with moderate/high delinquency. The relationship between high levels of delinquency and victimization was stronger for violence-related delinquency than for property-related delinquency.     

Work–family conflicts,cognitive appraisal,and burnout: Testing the mediation effect with structural equation modelling

Work–family conflict constitutes an important source of occupational stress predicting teachers’ burnout, and cognitive variables have shown to be core structures in explaining human adaptation to stress. Nevertheless, the role of cognitive appraisal needs to be fully analysed to comprehend how it can mediate the relationship between stress and burnout. In order to understand the potential mediation of cognitive appraisal in the relationship between stress and burnout, we adopted conceptual models of stress that highlighted the value of cognitive appraisal on positive and negative reactions to work demands. Also, we analysed the potential moderation of sex and age in the relationship between work–family conflict, cognitive appraisal, and burnout due to inconsistent findings on how these personal variables can interfere on these relations. In this study, we used structural equation modelling (SEM) to test the mediating of cognitive appraisal in the relationship between work–family conflicts and burnout. A survey with measures of work–family conflicts, cognitive appraisal, and burnout was administered to the participants consisting of 438 Portuguese teachers from kindergarten through high school, aged between 28 and 67 years (M = 46.85; SD = 7.88), 304 of whom were females (69.41%). The results confirmed that cognitive appraisal partially mediated the relationship between work–family conflict and burnout. The mediation effect of cognitive appraisal on the relationship between work–family conflict and burnout was invariant regardless of teachers’ sex or age. In sum, cognitive appraisal should be considered in order to understand teachers’ adaptation to work.     

State and Trait Anger Predicting Creative Process Engagement—The Role of Emotion Regulation

Drawing on the specific emotion approach, and based on the emotional regulation theory and cognitive and activation perspectives on emotions, this study examined the differentiated impact of state and trait anger on creative process engagement (CPE) and the moderating influences of emotion reappraisal and suppression. Data were obtained from daily surveys (N = 422) of 98 employees from three consultancy companies. Hierarchical linear modeling analysis revealed that trait anger has a stronger impact on CPE than state anger does. Furthermore, the relationship between state anger and CPE is stronger when emotion reappraisal is lower, rather than higher, and the relationship between trait anger and CPE is also stronger when emotion suppression is lower, rather than higher.