注意缺陷多动障碍反应抑制内表型研究

Study on response inhibition deficit serving as an endophenotype to ADHD

目的 探讨反应抑制能否作为注意缺陷多动障碍的认知内表现型.方法 运用反应/不反应任务、停止信号任务、Stroop色-字任务对100名注意缺陷多动障碍儿童和对照组儿童进行抑制功能测试,并收集注意缺陷多动障碍儿童的家族史.根据其家族史的有、无将注意缺陷多动障碍儿童分为家族史阳性组和家族史阴性组,运用多变量方差分析进行统计.结果 3组儿童在反应抑制功能上存在显著性差异[F（12,350）=7.916,P〈0.001,η2=0.213],控制FIQ后仍有统计学意义[F（12,348）=6.658,P〈0.001,η2=0.187].Bonferroni多重比较显示,在Stroop色-字测试反应时干扰及错误数干扰上,家族史阳性的注意缺陷多动障碍组儿童明显差于家族史阴性组,而后者又明显差于对照组儿童;在反应/不反应任务漏按键数、正确反应的反应时变异及停止信号任务的停止信号反应时上,两组注意缺陷多动障碍儿童明显差于对照组儿童,虽然两组注意缺陷多动障碍儿童间无显著性差异,但家族史阴性组表现介于家族史阳性组与对照组之间.结论 注意缺陷多动障碍儿童存在反应抑制功能缺陷;反应抑制可能是注意缺陷多动障碍的认知内表型之一.

Objective Attention deficit hyperactivity disorder （ADHD） is a polygenetic inheritance disease in which multiple genes interact with environmental factors in producing behavioral expression. Endophenotypes are influenced directly by the effects of genes and can increase the statistical power in genetic studies. The current study aimed to determine whether the deficit in response inhibition could serve as cognitive endophenotypes to ADHD. Methods One hundred children with ADHD and 100 healthy controls matched in age, gender, grade, handedness were conducted with neuropsychological tests concerning the domain of response inhibition （ go/no-go, stop signal task, Stroop color-word test）. The family history of ADHD was recorded among children with ADHD （probands） , and they were divided into two groups, ADHD children with positive family history and ADHD children with negative family history. The three groups were compared in the domain of response inhibition with multivariate analysis of variance （MANOVA）. Results The differences in response inhibition among three groups were significant [ F（ 12,350） = 7. 916, P 〈 0. 001, η2 = 0. 213 ], and they were still statistically significant after controlling full-scale intelligence quotient （FIQ） [ F（ 12,348 ） = 6. 658, P 〈 0. 001, η2 = 0. 187 ]. Bonferroni multiple comparisons showed that probands with family history of ADHD performed remarkably worse than those without family history of ADHD in interference indexes of reaction time and errors in Stroop color-word test, and the latter performed significantly worse than healthy controls. Both groups of children with ADHD performed worse than healthy controls in commission errors, the variability of reaction time in go/no-go task, stop-signal reaction time in stop signal task. Although there were no significiant differences between two ADHD groups, the performance of probands without family history of ADHD fell within the range between probands with family history of ADHD and healthy contrls. Conclusion There is deficit in response inhibition in children with ADHD. Response inhibition deficit may be one of cognitive endophenotypes to ADHD.