中文摘要：

目的：探讨注意缺陷多动障碍（ADHD）成年人在视觉搜索任务中不同工作记忆负荷下的注意特点。方法：选取45例符合美国精神障碍诊断与统计手册第4版（DSM-IV）诊断标准的成年人ADHD患者,以及44例年龄、性别、智商相匹配的健康成年人,通过工作记忆引导的视觉搜索任务来比较两组被试在低工作记忆负荷与高工作记忆负荷条件下的反应时与正确率。结果：在低工作记忆负荷[（823±144）ms vs.（754±123）ms,P〈0.01]与高工作记忆负荷[（912±163）ms vs.（851±162）ms,P〈0.01]条件下,成年人ADHD组的反应时均大于正常对照组。在两种任务中,低工作记忆负荷的反应时低于高工作记忆负荷下的反应时[ADHD患者,（823±144）ms vs.（912±163）ms,P〈0.01;对照,（754±123）ms vs.（851±162）ms,P〈0.01],低工作记忆负荷的正确率高于高工作记忆负荷下的正确率[ADHD患者,（95.9±4.3）% vs.（91.2±14.3）%;对照,（95.8±4.2）% vs.（94.4±4.9）%,P〈0.01]。结论：成年人ADHD患者在视觉搜索中存在自上而下注意缺陷。此外,视觉工作记忆负荷影响了ADHD患者的注意功能,当视觉工作记忆负荷增加时,注意资源相应减少,搜索效率降低。

英文摘要：

Objective：To explore the characteristics of attention during visual search tasks in adults with attention-deficit/hyperactivity disorder（ADHD）.Methods：Totally 45 adult patients with ADHD who met the Diagnostic and Statistical Manual of Mental Disorders,Fourth Edition（DSM-Ⅳ） and 44 healthy controls matched with age,gender and IQ were selected.The reaction time and accuracy rate of two groups were compared under visual search tasks of low and high visual working memory load.Results：The reaction time was longer in patients with ADHD than in the healthy controls in both low-load task[（823±144） ms vs.（754±123）ms,P〈0.01]and highload task[（912±163） ms vs.（851±162） ms,P〈0.01].Compared with the performance in low loadtask,the search reaction time was longer in high load task[ADHD group：（823±144） ms vs.（912±163） ms,P〈0.01;control group：（754±123） ms vs.（851±162） ms,P〈0.01]and the accuracy rate was lower during high load task than low load task[ADHD group：（95.9±4.3）% vs.（91.2±14.29）%;control group：（95.8±4.2）% vs.（94.4±4.9）%,P〈0.01]in both ADHD and control groups.Conclusion：The results suggest impairment in top-down attentional control in ADHD adults.When the visual working memory load is increasing,ADHD patients allocate more working memory resources on storing the target representation and less resources on visual attention,so the search efficiency may be influenced.