OBJECTIVETo explore the neuropsychological characteristics of children with attention deficit hyperactivity disorder (ADHD).

METHODSNeuropsychological tests, including visual working memory, Stroop test, digits inverse reciting, vocabulary fluency, Wisconsin card sort test (WCST), and Temporal discounting were used to evaluate the capacity of response inhibition, phonological working memory, visual working memory executive function and delayed satisfying capacity of subjects.

RESULTS1. The ADHD children spent longer time [ADHD-I (84(20), ADHD-C: 98 (31), normal: 70 (28)] to accomplish color naming and made more errors [ADHD-I: 3 (3), ADHD-C: 6 (19), normal: 2 (5)] than the normal control when the color was inconsistent with the word meaning in Stroop test (P < 0.01). 2. The scores of digits reciting [ADHD-I: 3 (3), ADHD-C: 3 (4), normal 4 (4)] inverse was lower in ADHD than in normal control (P < 0.01). 3. The representation of ADHD was poorer than normal control in visual working memory [ADHD-I: 21 (3), ADHD-C: 20 (5), Normal: 20 (3)], and in delayed visual memory [ADHD-I: 19 (5), ADHD-C: 19 (5), Normal: 20 (5)] (P < 0.01). 4. The scores of vocabulary fluency [ADHD-I: 1 (1), ADHD-C: 2 (1), normal: 0 (0)] was lower in ADHD than in normal control (P < 0.01). 5. In WCST, the ADHD children made more errors [ADHD-I :15 (17), ADHD-C: 15 (15), normal: 13 (13)] and less classification [ADHD-I: 5 (4), ADHD-C: 5 (4), normal: 5 (3)] than normal control (P < 0.01). 6. In Temporal discounting, the ADHD children showed significantly more impairments than normal control did (P < 0.01). 7. There was significant difference between the two subtype groups on some tests (P < 0.01).

CONCLUSIONSObvious cognitive impairments were found in children with ADHD, involving poor response inhibition, impaired working memory, dysfunction of planning and set-shifting, and there was no significant difference between the two subtype groups.