Developmental trends for object and spatial working memory: a psychophysiological analysis

This study examined developmental trends in object and spatial working memory (WM) using heart rate (HR) to provide an index of covert cognitive processes. Participants in 4 age groups (6-7, 9-10, 11-12, 18-26, n=20 each) performed object and spatial WM tasks, in which each trial was followed by feedback. Spatial WM task performance reached adult levels before object WM task performance. The differential developmental trends for object and spatial WM found in this study are taken to suggest that these WM components are separable. Negative performance feedback elicited HR slowing that was more pronounced for adults than for children. The development of performance monitoring as indexed by covert HR slowing following performance feedback contributes to WM performance.     

Cognitive brain potentials in kindergarten children with subtyped risks of reading retardation

Cognition-related brain responses to meaningful and meaningless figures were registered in 5-year-old kindergarten children who either had been subtyped as being at-risk of developing an L- or P-type dyslexia (LAL versus LAP) or who were not at-risk. While identifying, naming, or categorizing pictures, event-related potentials (ERP) were registered. Three cognition-related components were found: the N460, the P780, and the Slow Wave (SW). LAP-children produced weak N460 activity across tasks, whereas LAL children, and to a lesser degree, non-risk children produced robust task-dependent activity. This finding may indicate that LAP-children lack semantic input while processing the figures. P780 latencies to frequently occurring figures were found hemisphere-dependent: LAP-children showed longer latencies in the right than in the left hemisphere, whereas the distribution was reversed in the LAL and non-risk children. It was also found that the right hemisphere is generally responsible for a lion's share of the processing of figures and therefore it seems that the right hemisphere of LAP-children invests ample time in doing so. Whereas LAP-children showed largest SW amplitude differences between frequent and infrequent stimuli at posterior locations, LAL children did so at frontal locations. Assuming that the SW represents working-memory processes, it may be that working-memory in LAP-children deals with figure-relevant visual-spatial information and with figure-derived concepts in LAL children. Overall, the findings suggest that LAL and LAP represent two different groups of kindergartners at risk of dyslexia and that these differences, to some degree, fit with the presumed etiology of L- and P-type dyslexia.     

Barriers to prisoner participation in educational courses: Insights from a remand prison in Belgium

International Review of Education - This article examines the profile of prisoners who do not take part in formal education while being incarcerated (e.g. language or ICT courses) and the barriers...     

Refining Students’ Explanations of an Unfamiliar Physical Phenomenon-Microscopic Friction

Research in Science Education - The first phase of this multiphase study involves modeling of college students’ thinking of friction at the microscopic level. Diagnostic interviews were...     

The directional links between students’ academic motivation and social integration during the first year of higher education

European Journal of Psychology of Education - Previous theoretical research proposed a link between students’ academic motivation and students’ experiences of social integration, but...     

Effects of blood flow restriction without additional exercise on strength reductions and muscular atrophy following immobilization:A systematic review

Purpose:To investigate whether blood flow restriction(BFR) without concomitant exercise mitigated strength reduction and atrophy of thigh muscles in subjects under immobilization for lower limbs.Methods:The following databases were searched:PubMed,CINAHL,PEDro,Web of Science,Central,and Scopus.Results:The search identified 3 eligible studies,and the total sample in the identified studies consisted of 38 participants.Isokinetic and isometric torque of the knee flexors and extensors was examined in 2 studies.Cross-sectional area of thigh muscles was evaluated in 1 study,and thigh girth was measured in 2 studies.The BFR protocol was 5 sets of 5 min of occlusion and 3 min of free flow,twice daily for approximately 2 weeks.As a whole,the included studies indicate that BFR without exercise is able to minimize strength reduction and muscular atrophy after immobilization.It is crucial to emphasize,however,that the included studies showed a high risk of bias,especially regarding allocation concealment,blinding of outcome assessment,intention-to-treat analyses,and group similarity at baseline.Conclusion:Although potentially useful,the high risk of bias presented by original stodies limits the indication of BFR without concomitant exercise as an effective countermeasure against strength reduction and atrophy mediated by immobilization.     

A case of vitamin B12 deficiency neurological syndrome in a young adult due to late-onset cobalamin C (CblC) deficiency: a diagnostic challenge

Vitamin B12 deficiency can present with neurologic and psychiatric symptoms without macrocytic anaemia. We describe a case of late-onset cobalamin C deficiency which typically presents with normal serum vitamin B12 concentrations, posing an additional diagnostic challenge. A 23-year-old woman with decreased muscle strength and hallucinations was diagnosed with ‘catatonic depression’ and admitted to a residential mental health facility. She was referred to our hospital for further investigation 3 months later. Heteroanamnesis revealed that the symptoms had been evolving progressively over several months. Magnetic resonance imaging (MRI) of the brain showed diffuse symmetrical white matter lesions in both hemispheres. Routine laboratory tests including vitamin B12 and folic acid were normal except for a slight normocytic, normochromic anaemia. Over the next 6 weeks her symptoms deteriorated, and she became unresponsive to stimuli. A new MRI scan showed progression of the white matter lesions. The neurologist requested plasma homocysteine (Hcys) which was more than 8 times the upper limit of normal. Further testing revealed increased methylmalonic acid and the patient was diagnosed with adult-onset cobalamin C deficiency. This case illustrates that Hcys and/or methylmalonic acid should be determined in patients presenting with neuropsychiatric symptoms suggestive of vitamin B12 deficiency with a normal serum vitamin B12 to rule out a late-onset cobalamin C deficiency.