Muscular fitness,motor competence,and processing speed in preschool children

ABSTRACT

The aim of this study was to examine the relationship between muscular fitness and motor competence and processing speed in preschool children. Eighty-four preschool-aged children were recruited and underwent assessments for muscular fitness (muscular endurance and power), motor competence, and then participated in an auditory oddball task. The findings showed that muscular fitness and motor competence were associated with shorter reaction times after controlling for confounding factors. These findings provide tentative support for a positive association between muscular fitness and motor competence and processing speed in preschool children.

abbreviations:

Reaction time (RT); Institutional Review Board (IRB); Basic Motor Ability Test-Revised (BMAT); Body mass index (BMI); Preschool Children Fitness Programme (PCFP); Intraclass correlation coefficients (ICC); Thinking Creatively in Action and Movement test (TCAM); Inter-stimulus interval (ISI); Insulin-like growth factor 1 (IGF-1); Brain-derived neurotrophic factor (BDNF)     

Self-categorization and the explanation of ethnic discrimination

This study is concerned with majority group members' explanation of ethnic discrimination in Dutch society. The focus is on the causal structure and the type of attributions made. These issues are examined under two identity conditions: personal and national. It is found, first, that single-cause explanations that are typically studied in attribution research were used by only 7% of the participants. Second, the explanation of ethnic discrimination was affected by the level of self-categorization. In the national identity condition, majority group identification was related to the explanation of ethnic discrimination, whereas personal beliefs were related to the explanation given when personal identity was salient. Hence, in addition to the many factors that are taken into account in attribution research, both the causal structure and the question of how the self is defined when explanations are given should be considered. © 1998 John Wiley & Sons, Ltd.     

Stimulus control of the pigeon's ability to peck a moving target.

Two pigeons were trained to peck whichever of eight keys displayed a white field (SD). The other seven keys displayed a white "X" on a black background (S delta). Each peck to SD produced three-second access to grain, a three-second intertrial interval (ITI), and the next trial. Pecks to S delta produced a three-second timeout (TO) and the same trial. During later sessions the key displaying SD changed every t seconds (t = 3, 2, 1, .5, and .25 sec), requiring the birds to track the position of the SD. Pecks on a ninth key increased t. Several sessions employed novel stimuli to ascertain the controlling stimulus dimensions. Both birds made few errors acquiring the original discrimination. During the tracking sessions, both birds made few errors when t = .5 sec. Only one reliably lengthened t. Data from sessions with novel stimuli indicate that color and form were important aspects of SD and S delta respectively; movement contributed to the final performance.     

Language-experience facilitates discrimination of /d-th/ in monolingual and bilingual acquisition of English

To trace how age and language experience shape the discrimination of native and non-native phonetic contrasts, we compared 4-year-olds learning either English or French or both and simultaneous bilingual adults on their ability to discriminate the English /d-th/ contrast. Findings show that the ability to discriminate the native English contrast improved with age. However, in the absence of experience with this contrast, discrimination of French children and adults remained unchanged during development. Furthermore, although simultaneous bilingual and monolingual English adults were comparable, children exposed to both English and French were poorer at discriminating this contrast when compared to monolingual English-learning 4-year-olds. Thus, language experience facilitates perception of the English /d-th/ contrast and this facilitation occurs later in development when English and French are acquired simultaneously. The difference between bilingual and monolingual acquisition has implications for language organization in children with simultaneous exposure.     

A Brain-Based Account of the Development of Rule Use in Childhood

ABSTRACT— The ability to follow explicit rules improves dramatically during the course of childhood, but relatively little is known about the changes in brain structure and function that underlie this behavioral improvement. Drawing from neuroscientific studies in human adults and other animals, as well as from an emerging literature in developmental cognitive neuroscience, we propose a brain-based account of the development of rule use in childhood. This account focuses on four types of rules represented in different parts of the prefrontal cortex: simple rules for reversing stimulus–reward associations, pairs of conditional stimulus–response rules (both univalent and bivalent), and higher-order stimulus–response rules for selecting among task sets. It is hypothesized that the pattern of developmental changes in rule use reflects the different rates of development of specific regions within the prefrontal cortex.     

Risk and resilience: Dual effects of perceptions of group disadvantage among Latinos

Several decades of research on the psychology of minority status has yielded highly discrepant findings. Substantial research suggests that perceptions of discrimination are linked to inferior self-regard and poor mental health, whereas other studies indicate that perceptions of discrimination are protective of global self-esteem. We tested a theoretical model of the combined (negative/positive) effects of perceived group disadvantage on self-esteem among Latinos. Structural equation modeling analyses indicated that perceptions of group disadvantage were indirectly related to self-esteem through two principal pathways. The total (direct and indirect) effect on self-esteem was not significant, suggesting that, among Latinos, the deleterious consequences of perceived belonging to a devalued and disadvantaged group were fully counterbalanced by the positive effects of intervening variables. More complex models may be needed to characterize fully the self-protective and detrimental consequences of perceived group disadvantage among Latinos.     

Discrimination and religiosity among Muslim women in the UK before and after the Charlie Hebdo attacks

In January 2015, media outlets reported a series of attacks by Islamic terror groups in France, instigated at the offices of the Charlie Hebdo publication. Previous research has indicated that the consequence of exposure to terrorist attacks can extend beyond the immediate victims, with a potentially international reach. This secondary data analysis compares the perceptions of discrimination, religiosity, and religious engagement of 240 Muslim women in the UK, recruited before and after the Charlie Hebdo attacks. The results indicate greater religious engagement and perceptions of discrimination among those women recruited after the attacks. This suggests that the impact of such events may reach beyond the immediate victims, and societies need to develop and provide support in response to such attacks, regardless of the geographical location of the event.     

Visual exploration of reaching space during left and right arm movements in 6-month-old infants

Infant's manual laterality and eye-hand coordination emerge during the second part of the first year of life with the development of reaching. Nevertheless, little is known about the potential asymmetric characteristics of this coordination. The aim of this study was to describe visuo-spatial exploration in 6-month-old infants during reaching, according to the hand used. More specifically, we examined if the use of the left or the right hand was linked to a specific type of visual exploration. Gaze direction during goal-directed reaching towards an object placed on the table was measured with a remote ASL 504 eye tracker (Bedford MA). Twelve babies aged 6 months were observed during six reaching sessions, alterning three sessions with an object on the left side of the subject and three with an object on the right side. Gaze direction and some hand variables (hand activity, hand opening and hand position from the body) were coded with The Observer software. Results showed that babies visually explore their reaching space differently according to the hand used: they look more at the object when they use their right hand and more around the object when they use their left hand; they also look more often at their left hand than at their right one. These results suggest that an asymmetric visuo-manual coordination exists as early as 6 months: vision seems to support (1) left hand during reaching for evaluate distances from object to baby by means of visual feedbacks and (2) right hand for identify what sort of object is. Results are discussed in light of manual specialization and specific hemispheric skills at this age.     

Effect of task on mother-child interaction results

The influence of task on behavior in mother-child interaction was studied. Five tasks varying in degree of structure and difficulty were used in mothers' interactions with their children at 24 and 36 months of age. Child competence was assessed through several tests. Families that had participated in an extensive parent-education program were compared with randomly assigned controls. Interactions were videotaped and rated on scales. Results indicated that there were no task differences in ability to discriminate groups and tasks seldom were found to be differentially related to child competence. Task stability over time yielded some differences.This paper was presented at the American Educational Research Association meeting in Boston, April 1980. The preparation of this article and the research reported in it were supported by the Hogg Foundation, the Spencer Foundation, and Office of Child Development Grant 90-C-379.     

Category-specific visual agnosia: lesion to semantic memory versus extra-lesional variables in a case study and a connectionist model

There is a current debate on the causes of category-specific agnosia. The aim of this study was to examine the effects of lesional and extra-lesional variables on object recognition. Extra-lesional variables, such as visual complexity or familiarity, are factors that influence recognition. Using a connectionist model based on study, we provide evidence that extra-lesional variables can yield dissociations in the recognition rate of different categories. Furthermore, it is shown that lesional and extra-lesional variables can interact (p < .01) when both are simultaneously modeled. Category-specific agnosia might thus result from complex interactions.