ABSTRACT
Objective To explore the developmental characteristics of semantic processing of chil-dren with attention deficit hyperactivity disorder( ADHD) by comparing the event related potential in normal children and ADHD children ( ages 7-11 years old) .Methods 83 ADHD children and 93 normal children ranging from 7 to 11-year were divided into 5 groups to analyze the difference of the amplitude and latency of ERP N400 in three conditions:the related,unrelated and pesudoword after the Chinese character word visual stimulus task.Results (1) The related condition:the amplitude of the 7 years old normal children group was higher than 11 years old((-10.67±4.39)μV,(-4.62±3.55)μV;P=0.005);and the amplitude was highest in 8 years old group in children with ADHD( (-10.77±6.66) ms, F=2.54, P=0.046) .The latency in normal children was shorter at 8 years old((311.7±33.1) ms, P<0.05),but was shorter at 9 years old in ADHD group.( 2) The unrelated condition:the amplitude of normal children aged 10 years was higher than that of other age groups.( 3) The pesudoword condition:the amplitude of 9 years old normal children was higher than other age groups.The amplitude of ADHD in children aged 9 years was higher than that in other age groups( (-16.08±7.14)μV, P<0.05) .Conclusion In the semantic related conditions,the amplitude of the N400 in ADHD children at the age of 8 and the latency at the age of 9 are significantly developed,and in the false words conditions,it is at the age of 11.This suggests that the ability of 7-11 years old ADHD chil-dren's orthographic semantic processing and cognitive development are slower than normal.N400 can better reflect the children's early language cognitive ability,and it is valuable for the early diagnosis of children with ADHD.