Computer simulations of developmental change: the contributions of working memory capacity and long-term knowledge

Increasing working memory (WM) capacity is often cited as a major influence on children's development and yet WM capacity is difficult to examine independently of long-term knowledge. A computational model of children's nonword repetition (NWR) performance is presented that independently manipulates long-term knowledge and WM capacity to determine the relative contributions of each in explaining the developmental data. The simulations show that (a) both mechanisms independently cause the same overall developmental changes in NWR performance, (b) increase in long-term knowledge provides the better fit to the child data, and (c) varying both long-term knowledge and WM capacity adds no significant gains over varying long-term knowledge alone. Given that increases in long-term knowledge must occur during development, the results indicate that increases in WM capacity may not be required to explain developmental differences. An increase in WM capacity should only be cited as a mechanism of developmental change when there are clear empirical reasons for doing so.     

Tactile localization performance in children with developmental coordination disorder (DCD) corresponds to their motor skill and not their cognitive ability

When localizing touches to the hands, typically developing children and adults show a “crossed hands effect” whereby identifying which hand received a tactile stimulus is less accurate when the hands are crossed than uncrossed. This demonstrates the use of an external frame of reference for locating touches to one’s own body. Given that studies indicate that developmental vision plays a role in the emergence of external representations of touch, and reliance on vision for representing the body during action is atypical in developmental coordination disorder (DCD), we investigated external spatial representations of touch in children with DCD using the “crossed hands effect”. Nineteen children with DCD aged 7–11 years completed a tactile localization task in which posture (uncrossed, crossed) and view (hands seen, unseen) were varied systematically. Their performance was compared to that of 35 typically developing controls (19 of a similar age and cognitive ability, and 16 of a younger age but similar fine motor ability). Like controls, the DCD group exhibited a crossed hands effect, whilst their overall tactile localization performance was weaker than their peers of similar age and cognitive ability, but in line with younger controls of similar motor ability. For children with movement difficulties, these findings indicate tactile localization impairments in relation to age expectations, but apparently typical use of an external reference frame for localizing touch.     

Child vocational development: A review and reconsideration

Childhood marks the dawn of human development. To organize, integrate, and advance knowledge about vocational development during this age period from a life-span perspective, we conducted a comprehensive review of the empirical vocational development literature that addresses early-to-late childhood. The review considers career exploration, career awareness, vocational expectations and aspirations, vocational interests, and career maturity/adaptability. By conducting the review, we sought to consolidate knowledge and identify avenues for further research concerned with vocational development in childhood and across the life span. Linking knowledge of child vocational development with what is known about adolescent and adult vocational development and conducting research that embeds vocational development within the fabric of a life-span developmental framework could move the field of vocational psychology from a disjointed perspective on career as studied in isolated age groups and toward an integrated life-span conceptualization.     

Unilateral implicit motor learning deficit in developmental dyslexia

It has been suggested that developmental dyslexia involves various literacy, sensory, motor skill, and processing speed deficits. Some recent studies have shown that individuals with developmental dyslexia exhibit implicit motor learning deficits, which may be related to cerebellar functioning. However, previous studies on implicit motor learning in developmental dyslexics have produced conflicting results. Findings from cerebellar lesion patients have shown that patients' implicit motor learning performance varied when different hands were used to complete tasks. This suggests that dyslexia may have different effects on implicit motor learning between the two hands if cerebellar dysfunction is involved. To specify this question, we used a one-handed version of a serial reaction time task to compare the performance of 27 Chinese children with developmental dyslexics with another 27 age-matched children without reading difficulties. All the subjects were students from two primary schools, Grades 4 to 6. The results showed that children with developmental dyslexic responded more slowly than nondyslexic children, and exhibited no implicit motor learning in the condition of left-hand response. In contrast, there was no significant difference in reaction time between two groups of children when they used the right hand to respond. This finding indicates that children with developmental dyslexia exhibited normal motor skill and implicit motor learning ability provided the right hand was used. Taken together, these results suggested that Chinese children with developmental dyslexia exhibit unilateral deficits in motor skill and implicit motor learning in the left hand. Our findings lend partial support to the cerebellar deficit theory of developmental dyslexia.     

Externalizing behavior trajectories: The role of parenting, sibling relationships and child personality

Based on longitudinal multilevel modeling and using a multi-informant strategy, this study examines trajectories of externalizing problem behavior (EPB) in childhood as predicted by parental behavior (absolute level of parenting [ALP] and parental differential treatment [PDT]), parental self-efficacy (PSE), child personality and sibling relationships. Besides main effects, several interactions were tested. The effects of changes in parenting on changes in EPB were also examined. A total of 119 families from the French-speaking area of Belgium rearing a child (3- to 5-year-olds at the onset of the study) referred for EPB were studied. The effects of both level-of and changes-in mothers' ALP were partially confirmed, but for fathers, only ALP was predictive. There were some significant interactions between ALP and PDT for both parents. Mothers' PSE explained some variance in EPB, additional to that explained by the parenting measures. Some parenting by personality and by sibling relationship interactions were found.     

Dissecting online control in Developmental Coordination Disorder: a kinematic analysis of double-step reaching

In a recent study, children with movement clumsiness (or Developmental Coordination Disorder-DCD) were shown to have difficulties making rapid online corrections when reaching, demonstrated by slower and less accurate movements to double-step targets (Hyde & Wilson, 2011). These results suggest that children with DCD have difficulty using predictive estimates of limb position when making rapid adjustments to movement, in-flight. However, chronometric data alone does not provide strong evidence for this hypothesis: it remains unclear whether early (and rapid) control parameters or post-correction stages of the movement trajectory are affected. Thus, the overarching aim of this study was to conduct a kinematic analysis of double-step reaching in order to isolate the different control parameters that might explain the slower and less accurate double-step reaching performance of children with DCD. Participants were a new sample of 13 children with DCD aged between 8-12 years and 13 age-matched controls. Children were required to reach and touch one of three possible targets presented at the coordinates -20°, 0° and 20° on a 17 in. LCD touch-screen. For most trials (80%) the target remained stationary for the duration of movement (non-jump trials), while for the remainder (20%), the target jumped randomly to one of two peripheral locations at movement onset (jump trials). Consistent with earlier work, children with DCD were slower to initiate reaching compared to controls and showed longer MT and more errors on jump trials. Kinematic data showed that while the two groups did not differ on time to peak velocity or acceleration, children with DCD were slower to correct reach trajectory on jump trials. No group differences were observed on late kinematic markers, e.g., post-correction time. The pattern of results support and extend earlier work showing deficits in ROC in DCD. From a computational perspective, delayed corrections to the reach trajectory suggests some difficulty integrating information about the target perturbation with a predictive (or forward) estimate of limb position relative to the initial target. These conclusions are discussed, along with directions for future research.     

Parenting in relation to child and adolescent vocational development

Processes of child and adolescent vocational development include acquisition of knowledge, beliefs, and values about work options and requirements, exploration of interests that will be relevant for occupational interest development, development of academic aspirations, self-efficacy, expectations, and attainment. These elements serve to provide preparation for entry into a range of occupations and provide for the establishment of vocational aspirations, occupational self-efficacy, expectations, planning, and attainment. Parenting occurs within a family context influenced by a myriad of factors, including availability of financial capital, human capital, social capital, child agency, work-family interfacing, family roles, family structure, and the historical conditions affecting parents. These family contextual factors promote our understanding of differences in parenting in relation to child and adolescent vocational development. Far more complex than specific steps to entering the labor market per se, child and adolescent vocational development includes the interfacing of parenting and developmental processes.     

小学生口算能力的发展研究

研究目的是考察小学生口算速度和广度的发展。180名1至6年级城市小学生接受了口算能力的测验,结果显示：小学生口算的速度和广度随年级的增长而加快和扩大。不同口算的广度之问存在明显的差异,按口算广度的大小排列,依次是：不进位加法、不借位减法、进位加法、借位减法、除法和乘法。小学生口算的速度和广度均无显著的性别差异。数字广度和口算速度是制约口算广度的两个重要因素。     

The relationship between auditory temporal processing,phonemic awareness,and reading disability

Recent research suggests an auditory temporal deficit as a possible contributing factor to poor phonemic awareness skills. This study investigated the relationship between auditory temporal processing of nonspeech sounds and phonological awareness ability in children with a reading disability, aged 8-12 years, using Tallal's tone-order judgement task. Normal performance on the tone-order task was established for 36 normal readers. Forty-two children with developmental reading disability were then subdivided by their performance on the tone-order task. Average and poor tone-order subgroups were then compared on their ability to process speech sounds and visual symbols, and on phonological awareness and reading. The presence of a tone-order deficit did not relate to performance on the order processing of speech sounds, to poorer phonological awareness or to more severe reading difficulties. In particular, there was no evidence of a group by interstimulus interval interaction, as previously described in the literature, and thus little support for a general auditory temporal processing difficulty as an underlying problem in poor readers. In this study, deficient order judgement on a nonverbal auditory temporal order task (tone task) did not underlie phonological awareness or reading difficulties.     

Cultural differences in emotions: a context for interpreting emotional experiences

In this article, it is suggested that cross-cultural assessment of emotional disturbances would benefit from the consideration of cultural differences in the modal, and normative emotions. A summary of the research literature on cultural differences in emotions, in particular in antecedent events, subjective feeling, appraisal, and behavior is provided. Cultural differences in emotions are understood functionally, such that the most prevalent emotional phenomena in a culture are those that fit and reinforce the distinct cultural models (i.e. goals and practices) of self and relationship. It is argued that a culture-sensitive approach to emotional disturbances would entail the assessment of emotional phenomena that are dysfunctional to the cultural models of self and relationship.