Trajectories and predictors of indirect aggression: results from a nationally representative longitudinal study of Canadian children aged 2-10

The purposes of this study were to model the development of indirect aggression among a nationally representative sample of 1,401 Canadian children aged 4 at T2, 6 at T3, 8 at T4 and 10 at T5, and to examine predictors of trajectory group membership from T1 (age 2) child, familial, and parenting variables. Using a semi-parametric group-based modeling approach, two distinct trajectories were identified: "increasing users" comprising of 35% of the sample and "stable low users" comprising of 65% of the sample. Using logistic regression analyses to distinguish these two groups, we found that for girls, more frequent, increasing use of indirect aggression was associated with prior prosocial and physically aggressive behavior, low SES and low parental social support at age 2. For boys, increasing use of indirect aggression was associated with prior parenting issues at age 2-inconsistency and less positive parent-child interactions. Although this study provides unique information regarding the early development of indirect aggression and its predictors, more longitudinal research is needed to fully understand its development.     

Synthesis of asymmetric movement trajectories in timed rhythmic behaviour by means of frequency modulation

Results from different empirical investigations on gestural aspects of timed rhythmic movements indicate that the production of asymmetric movement trajectories is a feature that seems to be a common characteristic of various performances of repetitive rhythmic patterns. The behavioural or neural origin of these asymmetrical trajectories is, however, not identified. In the present study we outline a theoretical model that is capable of producing syntheses of asymmetric movement trajectories documented in empirical investigations by Balasubramaniam et al. (2004). Characteristic qualities of the extension/flexion profiles in the observed asymmetric trajectories are reproduced, and we conduct an experiment similar to Balasubramaniam et al. (2004) to show that the empirically documented movement trajectories and our modelled approximations share the same spectral components. The model is based on an application of frequency modulated movements, and a theoretical interpretation offered by the model is to view paced rhythmic movements as a result of an unpaced movement being “stretched” and “compressed”, caused by the presence of a metronome. We discuss our model construction within the framework of event-based and emergent timing, and argue that a change between these timing modes might be reflected by the strength of the modulation in our model.     

青少年早期冲动性的发展轨迹:界定亚群组及其影响因素

以发展的整体互动论和生态系统理论为基础,考察青少年早期冲动性的发展轨迹及其影响因素。采用Barratt冲动性量表、家庭环境量表、青少年感知校园氛围问卷对天津市某中学210名初中生进行了为期1年的3次追踪调查,使用潜变量增长模型、潜类别增长模型、多元Logistic回归进行数据分析。结果发现:(1)青少年早期冲动性的发展呈线性增长趋势,并可分为三个亚群组:恒低组(16.67%)、恒高组(41.43%)和居中升高组(41.91%);(2)家庭环境亲密度和教师支持对亚群组有显著预测作用。本研究揭示了在青少年早期冲动性的动态变化性、个体差异性及其相关影响因素。     

Homophobic bullying victimization trajectories: The roles of perpetration,sex assigned at birth,and sexuality

There is a paucity of research on developmental trajectories of bias-based aggression. We examined homophobic bullying victimization trajectories among high school students (N = 3,064; M age = 13.67; Girls = 50.2%) and how these developmental pathways vary as a function of factors like homophobic bullying perpetration, sex assigned at birth, and sexuality. Using data from a 3-wave longitudinal investigation over a 2-year period, we utilized latent growth mixture modeling to explore the aforementioned trajectories. Findings suggested that there were three distinct classes characterized by high initial rates and declines over time, low initial rates, and increases over time, and low, stable, rate across time. Furthermore, results indicated that homophobic bullying perpetration, sex assigned at birth, and sexuality all predicted class membership.     

Cognitive plasticity in successful ageing: contributions from a learning potential assessment / Plasticidad cognitiva en el envejecimiento exitoso: aportes desde la evaluación del potencial de aprendizaje

Abstract

Despite numerous studies on the subject of successful ageing, few studies address the issue from a learning potential (LP) perspective. In Latin America there is no empirical background describing LP in successful ageing. In this study, 157 elderly Argentines were categorized into ageing trajectories (successful, normal and pathological ageing) based on objective scores from autonomy level, cognitive performance and mood state scales. Subjects were assessed with classic neuropychological tests, a cognitive reserve scale and an LP test. The results show differences in LP and cognitive reserve according to different ageing trajectories. This study establishes a regional precedent of relevance in the study of LP in elderly people pursuing successful ageing. It also provides evidence of the usefulness of incorporating instances of delayed free recall and recognition in an episodic memory and LP test.     

Risk compensation theory and bicycle helmets – Results from an experiment of cycling speed and short-term effects of habituation

It has been suggested that the safety benefits of bicycle helmets are limited by risk compensation. The current study contributes to explaining whether the potential safety effects of bicycle helmets are reduced by cyclists’ tendency to cycle faster when wearing them (as a result of risk compensation), and if this potential reduction can be associated with a change in perceived risk. A previous study (Fyhri & Phillips, 2013) showed that non-routine helmet users did not increase their speed immediately after being given a helmet to wear, while routine helmet users cycled more slowly. The current study tests whether the previously found reduction in speed in response to helmet removal – as an indirect indicator of risk compensation – could be established in non-routine helmet users, after a period of habituation while cycling with a helmet.We did this by conducting a randomized crossover trial, in which we used GPS-derived speed calculations and self-reported risk perception. To test the effect of habituation, we used a design where each participant took part in two rounds with a break between and each round having two trips. We collected the data in June 2015. Non-routine helmet users (N = 31) were recruited in the field (along cycle routes in Oslo), and through a sample drawn from the Falck National register of bicycle owners. In the first phase of the study, all participants were asked to complete a test route (2.4 km downhill) with and without a helmet. In the second phase of the experiment, conducted after 1.5–2 h, the same participants again completed the test route with and without a helmet. In the time between the first and second phases of the experiment, all participants were given helmets, and told to use them on a predefined bicycle route.Habituation to the helmet between the first and second phases of the experiment did not produce any decrease (with helmet removal) in speed, on top of the habituation that occurred while cycling down the hill (the order effect). Mean speed difference for cycling with/without a helmet before the break was −0.76 km/h, after the break this difference was 0.32 km/h; 95% CIs [−0.5, 2.9] and [−0.9, 1.5]. We argue that risk compensation is an unlikely effect of using a bicycle helmet, and probably cannot explain any adverse effects related to helmet legislation.     

Relations with Parents and with Peers,Temperament, and Trajectories of Depressed Mood During Early Adolescence

The present study examined (a) whether groups of children can be empirically identified with distinct longitudinal profiles of depressed mood from late childhood through early adolescence, (b) to what extent these different longitudinal depression profiles are predicted by problematic relations with parents, same-sex peers, and other-sex peers, and (c) what role individuals' temperamental characteristics play in this context. Based on a sample of 414 early adolescents (197 girls), four groups were identified with distinct longitudinal profiles of depressed mood between ages 11 and 14: One group with consistently low levels of depressed mood, another with consistently moderate levels of depressed mood, a third group whose depressed mood increased sharply from late childhood through early adolescence, and a fourth group who already showed clinical-range levels of depressed mood during late childhood and whose depressive feelings increased even slightly more thereafter. Subsequent analyses revealed that rejection by same-sex peers was related to the odds of following an increasing trajectory of depressed mood, but only for girls with a highly reactive temperament. A problematic relationship with parents increased the odds of an elevated trajectory of depressed mood regardless of individual temperament. The theoretical and practical implications of these findings are discussed.     

The Development of Physical Aggression from Toddlerhood to Pre-Adolescence: A Nation Wide Longitudinal Study of Canadian Children

The objectives of the study were to model the developmental trajectories of physical aggression (PA) from toddlerhood to pre-adolescence and to identify risk factors that distinguish typical (normative) from atypical developmental patterns. Ten cohorts of approximately 1,000 children (n = 10,658) drawn form a nationally representative (Canadian) sample were followed over 6 years. Using a group based trajectory approach, we identified three groups of children with distinct developmental trajectories between 2 and 11 years of age. One third of the children (31.1%) followed a low desisting trajectory, reflected in infrequent use of PA in toddlerhood and virtually no PA by pre-adolescence. The majority of children (52.2%) followed a moderate desisting trajectory, reflected in occasional use of PA in toddlerhood and infrequent use by pre-adolescence. One sixth of the children (16.6%) followed a high stable trajectory of PA. Multivariate logistic regression indicated that children in the high PA trajectory group were more likely to be boys (OR: 1.67; CI: 1.5–1.87), from low income families (OR: 1.4; CI; 1.27–1.67), from families where the mother had not completed high school (OR: 1.20; CI: 1.05–1.38) and who reported using hostile/ineffective parenting strategies (OR: 1.16; CI: 1.14–1.18). In sum, the results indicate that the typical developmental pattern of PA was one of occasional and declining use over time. However, about one sixth of children, mostly boys from disadvantaged families, exhibited an atypical developmental pattern reflected in more frequent and stable use of PA. The results suggest that most children learned relatively well to inhibit PA by the end of childhood and that a minority failed to do so. Family risks traditionally found to be associated with antisocial behaviors during adolescence appear to interfere with the socialization of PA during early and middle childhood.