Working memory resources and children's reading comprehension

Reading and Writing - Working memory capacity is described as a pool of limited resources that carry out processing and storage functions. Its role has been emphasised in adults' reading...     

Influence of intertrial interval duration on the intertrial agreement effect in delayed matching-to-sample with pigeons

Accuracy on even-numbered trials was assessed as a function of (1) the relation between the sample on the immediately preceding trial and that on the current trial and (2) the length of the intertrial interval (ITI) that intervened between odd- and even-numbered trials. A relatively long interval intervened between pairs of trials in the clustered-dyads procedure, whereas this interval was equal to the ITI in the massed-trials procedure. Both procedures revealed an intertrial agreement effect in that accuracy was higher when the sample on the immediately preceding trial was identical rather than opposite. A decrease in the magnitude of this effect at longer ITIs was apparent only in the clustered-dyads procedure. The insensitivity of the intertrial agreement effect to variations in ITI in the massed-trials procedure may reflect floor effects and the carryover of memory from multiple prior trials that mask the true magnitude of the intertrial agreement effect at short ITIs.     

Effect of explicit problem solving instruction on high school students' problem-solving performance and conceptual understanding of physics

In this study a two-sample, pre/posttest, quasi-experimental design was used to investigate the effect of explicit problem-solving instruction on high school students' conceptual understanding of physics. Eight physics classes, with a total of 145 students, were randomly assigned to either a treatment or comparison group. The four treatment classes were taught how to use an explicit problem-solving strategy, while the four comparison classes were taught how to use a textbook problem-solving strategy. Students' problem-solving performance and conceptual understanding were assessed both before and after instruction. The results indicated that the explicit strategy improved the quality and completeness of students' physics representations more than the textbook strategy, but there was no difference between the two strategies on match of equations with representations, organization, or mathematical execution. In terms of conceptual understanding, there was no overall difference between the two groups; however, there was a significant interaction between the sex of the students and group. The explicit strategy appeared to benefit female students, while the textbook strategy appeared to benefit male students. The implications of these results for physics instruction are discussed. © 1997 John Wiley & Sons, Inc. J Res Sci Teach 34: 551–570, 1997.     

Stability of the Kaufman Assessment Battery for Children For A Sample Of At-Risk Preschool Children

This study examined the stability of the Kaufman Assessment Battery for Children (K-ABC) for a sample of at-risk preschool children. Over a 9-month time interval, the stability coefficients (corrected for restriction in range) for the global scales of the K-ABC ranged from .78 to .88. The stability coefficients (corrected for restriction in range) for the K-ABC subtests ranged from .65 to .79. It was concluded that scores on the K-ABC for at-risk preschool children display adequate stability, but that the Simultaneous scale appears to be more amenable to change than either the Sequential or Achievement scales.     

Reliability of the Boehm Test of Basic Concepts for Hispanic and nonHispanic kindergarten pupils

The internal consistency reliability of the Boehm Test of Basic Concepts (BTBC) was examined for 40 Hispanic and 40 non Hispanic kindergarten pupils in the Southwest. Subscale and total scale reliabilities appeared to be comparable. This evidence supported the reliability of the BTBC for Hispanic and non Hispanic kindergarten pupils.     

Contralateral limb deficit after ACL-reconstruction: an analysis of early and late phase of rate of force development

The aim of this study was to assess the effect of a unilateral anterior cruciate ligament reconstruction (ACLR) on maximum voluntary contraction (MVC) and explosive strength of both the involved limb and the uninvolved limb. Nineteen male athletes completed a standard isometric testing protocol 4 months post-ACLR, while 16 healthy participants served as a control group (CG). The explosive strength of the knee extensors and flexors was assessed as RFD obtained from the slope of the force–time curves over various time intervals. Both muscle groups of the involved limb had significantly lower MVC compared to the uninvolved. The involved limb also had significantly lower RFD in the late phase of contraction (140–250 ms) for both knee extensors and flexors (P < 0.05). There was no difference in MVC between the uninvolved limb and the CG. However, RFD of the uninvolved limb was lower compared to CG for both knee extensors (0–180 ms; P < 0.01) and flexors (0–150 ms; P < 0.05). ACLR leads to lower MVC and explosive strength of the involved limb. As a consequence of potential crossover (presumably neural-mediated) effects, explosive strength deficits could be bilateral, particularly in the early phase of the contraction (<100 ms).     

The impact of badminton on health markers in untrained females

The purpose of the study was to examine the health effects of 8 weeks of recreational badminton in untrained women. Participants were matched for maximal oxygen uptake (V?O_2max) and body fat percentage and assigned to either a badminton (n = 14), running (n = 14) or control group (n = 8). Assessments were conducted pre- and post-intervention with physiological, anthropometric, motivation to exercise and physical self-esteem data collected. Post-intervention, V?O_2max increased (P < 0.05) by 16% and 14% in the badminton and running groups, respectively, and time to exhaustion increased (P < 0.05) by 19% for both interventions. Maximal power output was increased (P < 0.05) by 13% in the badminton group only. Blood pressure, resting heart rate and heart rate during submaximal running were lower (P < 0.05) in both interventions. Perceptions of physical conditioning increased (P < 0.05) in both interventions. There were increases (P < 0.05) in enjoyment and ill health motives in the running group only, whilst affiliation motives were higher (P < 0.05) for the badminton group only. Findings suggest that badminton should be considered a strategy to improving the health and well-being of untrained females who are currently not meeting physical activity guidelines.