Use of cognitive correction training improves learning for children with mathematics learning disability.

Children with normal intelligence may experience varying degrees of mathematics learning disabilities (MD). This study aims to conduct training to improve the brain's cognitive ability for mathematics learning by focusing on two important mathematical cognitive abilities. This was a prospective study of 70 children in grades 2-5 from two primary schools in Changzhou and with MD enrolled from June 2015 to February 2017. The children were randomized 1:1 to the training and control groups. A training cycle included 40 sessions (5/weeks) (30 min each session). The efficacy of learning was assessed by assessing number learning and graph reasoning, and by using the Raven standard reasoning test score. In the training group, backward number memory (from 6.1 ± 1.8 to 6.7 ± 1.3, P = 0.02), number sequential connection (from 54.4 ± 14.5 to 47.1 ± 12.1, P < 0.01), and rapid graph judgment (from 531.9 ± 76.3 to 557.8 ± 85.7, P = 0.04) were improved by training, while there was no effect on forward number memory (P = 0.13). There were significant differences in total score and scores of b, c, and e series before and after training (all P < 0.05). The children in the control group had no improvement after 8 weeks. There was a correlation between the ability of rapid graphic judgment before and after training and the score of the Raven E series (r = 0.384, P = 0.024), and between the score of the Raven C series and the score of the Raven D series (r = 0.468, P = 0.013). Cognitive correction training improved the sensitivity to numbers and mathematics learning in children with MD.

Functional network connectivity changes in children with attention-deficit hyperactivity disorder: A resting-state fMRI study.

The study aimed to investigate the pathologic mechanism of functional brain regions in attention-deficit hyperactivity disorder (ADHD) patients through making comparisons of normal and ADHD children from the perspective of the network nodes of brain network and the intensity of functional connection between bilateral of hemispheres by resting-state functional magnetic resonance imaging (fMRI). Thirty-five ADHD and forty-two children were examined by resting-state functional magnetic resonance imaging (fMRI) scans. Data analysis was done via the degree centrality (DC) and voxel-mirrored homotopic connectivity (VMHC) approaches. Compared with healthy subjects, the ADHD group exhibited significantly decreased DC values in the right posterior cingulate gyrus, left medial superior frontal gyrus, right inferior parietal gyrus, right middle frontal gyrus, left superior frontal gyrus and right superior frontal gyrus. Children with ADHD also exhibited some areas with increased DC values compared with healthy children. These regions included the cerebellar anterior lobe, right middle occipital cortex, left middle cingulate gyrus and right middle cingulate gyrus. VMHC analysis all revealed positive activation in a range of brain regions when comparing ADHD and normal children, suggesting that the VMHC scores of children with ADHD were higher in the bilateral superior frontal lobe, bilateral middle occipital lobe, and bilateral cerebellar anterior lobes. This work provides a new approach for examining the neural mechanisms underlying ADHD, demonstrating that the DC and VMHC methods enabled more comprehensive analysis that can be cross-checked.

[Event-related potentials of working memory impairment in children with primary nocturnal enuresis].

OBJECTIVE: To study the cognitive neural mechanism of working memory impairment in children with primary nocturnal enuresis using event-related potential (ERP). METHODS: A total of 14 children with primary nocturnal enuresis were enrolled as enuresis group, and 14 normal children were enrolled as control group. The learning-recognition task test was applied, and the ERP components (P2, N2, and P3) at Fz lead while identifying old pictures (learned) and new ones (unlearned) were measured and compared between the two groups. RESULTS: While identifying the old pictures, the enuresis group had a lower amplitude of P2 and N2 than the control group (P<0.05). There were no significant differences between the two groups in the latency of P2, N2, and P3 and the amplitude of P3. While identifying the new pictures, the enuresis group had a longer latency of P2 and a significantly lower amplitude of N2 than the control group (P<0.05). There were no significant differences between the two groups in the amplitude of P2 and P3 and the latency of N2 and P3. CONCLUSIONS: Compared with normal children, the children with primary nocturnal enuresis have reduced abilities of classified information extraction, a prolonged reaction time, and reductions in memory capacity, memory consolidation, and conflict monitoring, which causes working memory impairment.

Degree centrality and voxel-mirrored homotopic connectivity in children with nocturnal enuresis: A functional MRI study.

AIM: To determine the characteristics of brain development in children with nocturnal enuresis, we investigated the intensity of functional connectivity both among the nodes in the brain network and between the two hemispheres of the brain. MATERIALS AND METHODS: Twenty-three children with nocturnal enuresis (NE) and an equal number of normal children were examined using resting-state functional magnetic resonance imaging (fMRI) scans. Data analysis was done via the degree centrality (DC) and voxel-mirrored homotopic connectivity (VMHC) approaches. Moreover, we compared the children's psychological status by utilizing the self-concept scale. RESULTS: In four areas of the brain, the the DC values of the NE group were obviously lower than that of the normal controls. These four areas were the posterior cerebellar lobe, anterior cingulate cortex (ACC), medial frontal gyrus, and superior left temporal gyrus (P < 0.05, after correction). We also found two brain areas where the VMHC values of the NE group were obviously lower than that of the normal controls. The two groups were the cerebellar lobe and the anterior cingulate cortex (ACC) [P < 0.05, after correction]. A psychological comparison between the children with NE and that in the normal group on the self-concept scale was also performed. The scores of the children with NE were lower than normal controls regarding behavior, appearance and property, anxiety, gregariousness, happiness, and satisfaction (P < 0.05). CONCLUSIONS: These findings provide evidence of the deficit of urination control in children with NE. Furthermore, through the methods of DC and VMHC, which are based on functional connectivity, it was also possible to explain why children with NE often have the concomitant symptoms of attention, control, and memory problems. The analysis of the self-concept scale suggests that children with NE lack self-confidence.

[Correlation between event-related potential and behavioral problems in early school-age children with attention deficit hyperactivity disorder].

OBJECTIVE: To investigate the cognitive characteristics in early school-age children with attention deficit hyperactivity disorder (ADHD) using event-related potential (ERP) and Achenbach Child Behavior Checklist (CBCL), as well as the correlation between ERP and behavioral problems. METHODS: A total of 22 children aged 6-7 years with ADHD and 19 healthy children matched by age were enrolled. Continue Performance Test-AX (CPT-AX) was performed for ERP test. The amplitude and latency of N2 and P3 of Go and Nogo were compared. The CBCL was completed by the parents, and the correlation between behavioral factors and ERP was analyzed. RESULTS: The ADHD group had a significantly higher number of ERP omissions than the normal control group (10±8 vs 5±4; P<0.05), while the reaction time and number of commission errors showed no significant differences between the two groups (P>0.05). The ADHD group showed a significantly lower Go-N2 amplitude than the normal control group (-8±5 µV vs -10±4 µV; P<0.05). In the ADHD group, the detection rates of hyperactivity, attack, and discipline violation were 27%, 27% and 9% respectively. The scores on attack and discipline violation subscales were negatively correlated with the Go-N2 amplitude of ERP (r=-0.43 and -0.48 respectively; P<0.05), while the score on hyperactivity subscale was positively correlated with the latency of Go-P3 (r=0.50, P<0.05). CONCLUSIONS: The early school-age children with ADHD show the tendency to the impairment of attention/executive function, but the inhibition function defect has not been noted. In early school-age children with ADHD, the behavioral problems such as hyperactivity, attack, and discipline violation are associated with ERP.

[Event-related potential and behavioral characteristics in children with attention deficit hyperactivity disorder of different school entrance ages: a comparative study].

OBJECTIVE: To evaluate the effects of school entrance age on cognition and behaviors in children with attention deficit hyperactivity disorder (ADHD) using mathematical event-related potential (ERP), behavioral test, and Conners Parent Symptom Questionnaire (PSQ). METHODS: Fifty-eight ADHD children aged 7-12 years were enrolled and classified into older age and younger age groups according to the school entrance age (n=29 each). The children in the older age group were admitted at an age of 6 years and 6 months to 6 years and 11 months, and those in the younger age group were admitted at an age of 6 years to 6 years and 5 months. The ERP with a mathematical task was used to detect the difference in brain electrical activity between the two groups, and the behavioral test results were compared. The children's parents were asked to complete the PSQ, and the scores on each subscale were compared. RESULTS: The ERP detection showed that the older age group had a significantly higher P2 amplitude for wrong answers than the younger age group (10.9±5.0 µv vs 8.5±3.6 µv; P<0.05). The younger age group had a significantly shorter time of response to wrong answers than the older age group (619±340 ms vs 870±418 ms; P<0.05). The scores on the subscales of learning problems and impulse-hyperactivity of PSQ were significantly higher in the younger age group than in the older age group (P<0.05). CONCLUSIONS: School entrance age can affect cognition and behaviors in children with ADHD, and the ADHD children with a younger school entrance age have an obvious defect in executive function, especially the function of error detection, which leads to the prominent problems in impulse-hyperactivity and learning.

Tannic Acid as a Bio-Based Modifier of Epoxy/Anhydride Thermosets.

Toughening an epoxy resin by bio-based modifiers without trade-offs in its modulus, mechanical strength, and other properties is still a big challenge. This paper presents an approach to modify epoxy resin with tannic acid (TA) as a bio-based feedstock. Carboxylic acid-modified tannic acid (TA⁻COOH) was first prepared through a simple esterification between TA and methylhexahydrophthalic anhydride, and then used as a modifier for the epoxy/anhydride curing system. Owing to the chemical modification, TA⁻COOH could easily disperse in epoxy resin and showed adequate interface interaction between TA⁻COOH and epoxy matrix, in avoid of phase separation. The use of TA⁻COOH in different proportions as modifier of epoxy/anhydride thermosets was studied. The results showed that TA⁻COOH could significantly improve the toughness with a great increase in impact strength under a low loading amount. Moreover, the addition of TA⁻COOH also simultaneously improved the tensile strength, elongation at break and glass transition temperature. The toughening and reinforcing mechanism was studied by scanning electron microscopy (SEM), dynamic mechanical analysis (DMA) and thermal mechanical analysis (TMA), which should be owned to the synergistic effect of good interface interaction, aromatic structure, decreasing of cross linking density and increasing of free volume. This approach allows us to utilize the renewable tannic acid as an effective modifier for epoxy resin with good mechanical and thermal properties.