Event-related potential and behavioral characteristics in children with attention deficit hyperactivity disorder of different school entrance ages: a comparative study / 中国当代儿科杂志

<p><b>OBJECTIVE</b>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).</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSIONS</b>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.</p>

Correlation between event-related potential and behavioral problems in early school-age children with attention deficit hyperactivity disorder / 中国当代儿科杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSIONS</b>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.</p>