注意缺陷多动障碍儿童的内隐视觉空间注意特点

摘要

目的:探讨注意缺陷多动障碍(ADHD)儿童被动和主动内隐视觉空间注意特点.方法:选取符合美国精神障碍诊断与统计手册第4版(DSM-Ⅳ)ADHD诊断标准的儿童25例,以及性别、年龄与之匹配的正常儿童18名.分别测试反映被动内隐视觉空间注意的pop-out视觉搜索任务及反映主动内隐视觉空间注意的线索-目标视觉搜索任务,比较两组反应时(RT)、正确率和个体内反应时标准差(ISD).结果:Pop-out视觉搜索任务中,ADHD儿童[(637.4±132.0) ms vs.(626.3±125.0) ms]和正常儿童[(635.5±131.1) ms vs.(626.6±138.5) ms]对左视野目标反应时均长于右视野(均P＜0.05),但是两组之间反应时、总体正确率差异无统计学意义(均P ＞0.05)；正常儿童左视野正确率低于右视野[(92.3±9.4)％ vs.(94.5±8.1)％,P＜0.01],而ADHD儿童左右视野正确率差异无统计学意义[(91.9±7.4)％ vs.(90.7±7.5)％,P＞0.05],ADHD儿童ISD大于正常儿童[(185.4±48.0) ms vs.(137.5±36.7) ms,P＜0.01].线索-目标任务中,ADHD儿童和正常儿童对左视野的目标反应时均长于右视野[ADHD组,(641.1 ±94.2) ms vs.(629.1 ±83.1)ms;正常对照组,(626.3±128.6) ms vs.(614.9±133.1)ms;均P＜0.05],且线索提示有效目标反应时短于线索提示无效[ADHD组,(627.6±89.4) msvs.(654.3±84.6)ms,P＜0.01;正常对照组,(615.4±132.5) ms vs.(627.3 ±127.5) ms,P＜0.01]；两组之间反应时和正确率差异无统计学意义,ADHD儿童ISD大于正常儿童[(200.1±46.8) ms vs.(147.8±32.8)ms,P=0.05].结论:与正常儿童相比,ADHD儿童无论是被动还是主动内隐视觉空间注意,其注意力状态均不稳定,波动性增大,注意力维持困难.%Objective:To investigate the characteristic of bottom-up and top-down visual spatial attention in children with attention-deficit/hyperactivity disorder (ADHD).Methods:Twenty-five drug-naive children with ADHD meeting the criteria of the Diagnostic and Statistical Manual of Mental Disorders,Fourth Edition (DSM-Ⅳ) and 18 age-and gender-matched normal children were recruited.They performed the pop-out and cue-target visual search task which were designed to test the covert reflexive attention and covert effortful attention respectively.The differences in reaction times (RT),accuracy rates and intra-individual standard deviation of RT (ISD) between the two groups were compared.Results:In pop-out visual search task,children with ADHD [(637.4 ± 132.0) ms vs.(626.3 ± 125.0) ms] and normal controls [(635.5 ± 131.1) ms vs.(626.6 ± 138.5) ms] both had longer RT to left visual field (RVF) target than to right visual field (LVF) target (Ps ＜0.05),while no differences were found between the two groups.The normal children had lower accuracy rates to LVF target than RVF target [(92.3 ± 9.4) ％ vs.(94.5 ± 8.1) ％,P ＜ 0.01],while no differences were found between LVF target and RVF target in children with ADHD [(91.9 ±7.4)％ vs.(90.7 ±7.5)％,P ＞0.05].The ISD was higher in children with ADHD than in normal children [(185.4 ±48.0) ms vs.(137.5 ±36.7) ms,P =0.001].In cue-target visual search task,both children with ADHD and normal children had shorter RT to RVF target than LVF target [ADHD group,(629.1 ±83.1) ms vs.(641.1 ±94.2) ms,P ＜0.05] ; normal control group,[(614.9 ± 133.1) ms vs.(626.3 ±128.6) ms,P ＜ 0.05] and shorter RT to validly cued target than invalidly cued target[ADHD group,(627.6 ±89.4) ms vs.(654.3 ± 84.6) ms,P ＜ 0.01; normal control group,(615.4 ± 132.5) ms vs.(627.3 ± 127.5) ms,P ＜ 0.01].There were no differences in RT and accuracy rates between the two groups.The ISD was higher in children with ADHD than in normal children [(200.1 ±46.8) ms vs.(147.8 ± 32.8) ms,P ＜0.01].Conclusion:It suggests that the attention state may be unstable and fluctuation significantly increases in children with ADHD compared with normal children.It may be difficult for ADHD children to maintain attention in completing covert reflexive and effortful visual spatial attention.