Number processing and calculation in Brazilian children aged 7-12 years

Numerical cognition is based on two components - number processing and calculation. Its development is influenced by biological, cognitive, educational, and cultural factors. The objectives of the present study were to: i) assess number processing and calculation in Brazilian children aged 7-12 years from public schools using the Zareki-R (Battery of neuropsychological tests for number processing and calculation in children, Revised; von Aster & Dellatolas, 2006) in order to obtain normative data for Portuguese speakers; ii) identify how environment, age, and gender influences the development of these mathematical skills; iii) investigate the construct validity of the Zareki-R by the contrast with the Arithmetic subtest of WISC-III. The sample included 172 children, both genders, divided in two groups: urban (N = 119) and rural (N = 53) assessed by the Zareki-R. Rural children presented lower scores in one aspect of number processing; children aged 7-8 years demonstrated an inferior global score than older; boys presented a superior performance in both number processing and calculation. Construct validity of Zareki-R was demonstrated by high to moderate correlations with Arithmetic subtest of WISC-III. The Zareki-R therefore is a suitable instrument to assess the development of mathematical skills, which is influenced by factors such as environment, age, and gender.     

A neurocomputational approach to obsessive-compulsive disorder

A recent article shows that a change in a single parameter in a neural-network model of brain dynamics leads to repetitive behaviors that resist termination and towards which the network tends. These findings may have implications for obsessive-compulsive disorder and are consistent with evidence of glutamatergic hyperactivity in this disorder.     

The Temporal and Dynamic Nature of Self-Regulatory Processes During Independent and Externally Assisted Hypermedia Learning

This study examined the temporal and dynamic nature of students’ self-regulatory processes while learning about the circulatory system with hypermedia. A total of 74 undergraduate students were randomly assigned to 1 of 2 conditions: independent learning or externally assisted learning. Participants in the independent learning condition used a hypermedia environment to learn about the circulatory system on their own, while participants in the externally assisted condition used the same hypermedia environment, but were given prompts and feedback from a human tutor during the session to facilitate their self-regulatory behavior. Previously published pretest–posttest shifts toward more mature understanding of the circulatory system indicate that the externally assisted condition leads to greater learning. The present article uses think-aloud data during learning to explore process issues in light of models of self-regulated learning and conditions of engagement that may affect those processes. Results indicate that access to a human tutor influences the deployment of regulatory processes, intervals of use, and temporal dependencies. For example, there is significantly more planning during the final time interval of the learning session in the externally assisted condition; students in both conditions deploy more learning strategies in the first and second time intervals, compared to the last two time intervals. Additionally, in the externally assisted condition participants were more likely to shift from planning to monitoring and less likely to shift from learning strategies to planning. We discuss theoretical, conceptual, and methodological issues pertaining to these results, as well as implications for future research and the design of adaptive hypermedia systems.     

Characterization of speed fluctuation and drag force in young swimmers: A gender comparison

The aim of this study was to compare the speed fluctuation and the drag force in young swimmers between genders. Twenty-three young pubertal swimmers (12 boys and 11 girls) volunteered as subjects. Speed fluctuation was measured using a kinematical mechanical method (i.e., speedo-meter) during a maximal 25-m front crawl bout. Active drag, active drag coefficient and power needed to overcome drag were measured with the velocity perturbation method for another two maximal 25 m front crawl bouts with and without the perturbation device. Passive drag and the passive drag coefficient were estimated using the gliding decay velocity method after a maximal push-off from the wall while being fully immersed. The technique drag index was also assessed as a ratio between active and passive drag. Boys presented meaningfully higher speed fluctuation, active drag, power needed to overcome drag and technique drag index than the girls. There were no significant gender differences for active drag coefficient, passive drag and passive drag coefficient. There were positive and moderate-strong associations between active drag and speed fluctuation when controlling the effects of swim velocity. So, increasing speed fluctuation leads to higher drag force values and those are even higher for boys than for girls.     

Levels of immersion, tacit knowledge and expertise

This paper elaborates on the link between different types and degrees of experience that can be gone through within a form of life or collectivity—the so-called levels of immersion—and the development of distinct types of tacit knowledge and expertise. The framework is then probed empirically and theoretically. In the first case, its ‘predictions’ are compared with the accounts of novices who have gone through different ‘learning opportunities’ during a pre-operational training programme for running a huge nickel industrial plant in Brazil. These are also analysed vis-à-vis the experience of an expert who has designed and experienced the outcomes of two pre-operational training sessions in the nickel industry before developing and managing the one discussed here. Theoretically, the framework is used to pinpoint exactly what interactional experts who have developed their expertise through linguistic socialisation alone are able to do as well as to analyse the case of technical connoisseurs. The results indicate that the proposed framework is useful. It supports the design and improvement of training programmes for the development of tacit knowledge while at the same time bringing about a refined analysis of claims concerning the abilities of types of experts and expertise.     

Evidence of precurrent responses expanding equivalence classes in a delayed matching-to-sample task

Delayed matching to sample (DMTS) increases the probability of equivalence class formation. Precurrent responses can mediate the retention interval in DMTS trials and control the selection of comparisons. In human participants, precurrent responses usually consist of naming the experimental stimuli based on their similarities to meaningful stimuli with preexperimental history. We tested whether precurrents expand classes by serving as nodes between experimental and meaningful stimuli. A DMTS (2 s) was used throughout the entire experiment. Eleven undergraduates learned A1B1 and A2B2 relations and then were submitted to ArC trials that required them to answer math problems presented during the DMTS interval: when the sample was A1, the problems resulted in 12 and C1 was correct; when the sample was A2, they resulted in 9 and C2 was correct. Response-as-node tests assessed whether participants would relate B1 and C1 to the printed number 12 and B2 and C2 to the printed number 9. Ten participants responded accordingly to this pattern, showing that the responses to the problems expanded the classes. Parity tests using the words “even” and “odd” further confirmed this hypothesis. These results contribute to understanding why DMTS enhances equivalence performances. Implications of using this procedure in stimulus-equivalence studies are discussed.     

Child and adolescent psychopathy: Assessment issues and treatment needs

The identification of psychopathic traits in childhood and adolescence is a topic of growing interest for scientific research. The development of models to predict violent behavior, together with efficient preventive and therapeutic programs, is a major goal when assessing youths with psychopathic traits. This paper focuses on the construct of child and adolescent psychopathy, while approaching historical and conceptual issues. By discussing the “state of the art” of the construct, we will analyze different instruments to assess psychopathy in children and adolescents, as well as the available treatment modalities. Finally, we will present possible lines for research and clinical intervention according to an evolutionary approach to anger and antisocial behavior.     

Is time limit at the minimum swimming velocity of VO2 max influenced by stroking parameters?

The aim of this study was to observe the relationship between time limit at the minimum velocity that elicits maximal oxygen consumption (TLim-v VO2 max) and stroke rate, stroke length, and stroke index. 13 men and 10 women, highly trained swimmers, performed an intermittent incremental test for v VO2 max assessment and an all-out swim to estimate TLim-v VO2 max. The mean +/- SD TLim-v VO2 max, v VO2 max, stroke rate, stroke length, and stroke index values were 233.36 +/- 53.92 sec., 1.40 +/- .06 meter/sec., 35.58 +/- 2.89 cycles/min., 2.39 +/- .22 meter/cycle, and 3.36 +/- .41 meter2/(cycle x sec.), respectively. The correlation between TLim-v VO2 max and stroke rate was -.51 (p < .01), and values for TLim-v VO2 max with stroke length (r = .52, p < .01) and stroke index (r = .45, p < .05). These results seem to suggest that technical skill is a key factor in typical efforts requiring prolonged aerobic power.     

Measures of infant self-regulation during the first year of life: A systematic review

This study aimed to systematically review the measures used to assess infant self-regulation during the first 12 months of life. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement protocol. From 235 selected papers, 79 provided information on behavioural and physiological measures to assess infant self-regulation during the first 12 months of life. Thirty-six behavioural (30 observational and 6 parent-report) and five physiological different measures were identified. Studies with a longitudinal design, comprising larger samples, and aiming to assess infant self-regulation later in infancy, mostly used behavioural measures than physiological measures. Studies comprising lower samples and aiming to assess infant self-regulation earlier in infancy, mostly used observational than parent-reported measures. Studies targeting younger infants used physiological measures and studies targeting older infants used behavioural measures, with observational measures used with younger infants and parental-reported measures used with older infants during the first year of life. When measuring self-regulation is important to consider infant's age, to fit the measurement procedures with the self-regulation development level.