Kennedy Krieger Institute, 716 N. Broadway, Baltimore, MD 21205, USA.
J Am Acad Child Adolesc Psychiatry. 2011 Jul;50(7):705-715.e3. doi: 10.1016/j.jaac.2011.03.014. Epub 2011 Jun 11.
Attention-deficit/hyperactivity disorder (ADHD) is associated with difficulty inhibiting impulsive, hyperactive, and off-task behavior. However, no studies have examined whether a distinct pattern of brain activity precedes inhibitory errors in typically developing (TD) children and children with ADHD. In healthy adults, increased activity in the default mode network, a set of brain regions more active during resting or internally focused states, predicts commission errors, suggesting that momentary lapses of attention are related to inhibitory failures.
Event-related functional magnetic resonance imaging and a go/no-go paradigm were used to explore brain activity preceding errors in 13 children with ADHD and 17 TD controls.
Comparing pre-error with pre-correct trials, TD children showed activation in the precuneus/posterior cingulate cortex and parahippocampal and middle frontal gyri. In contrast, children with ADHD demonstrated activation in the cerebellum, dorsolateral prefrontal cortex (DLPFC), and basal ganglia. Between-group comparison for the pre-error versus pre-correct contrast showed that children with ADHD showed greater activity in the cerebellum, DLPFC, and ventrolateral PFC compared with TD controls. Results of region-of-interest analysis confirmed that the precuneus/posterior cingulate cortex are more active in TD children compared with children with ADHD.
These preliminary data suggest that brain activation patterns immediately preceding errors differ between children with ADHD and TD children. In TD children, momentary lapses of attention precede errors, whereas pre-error activity in children with ADHD may be mediated by different circuits, such as those involved in response selection and control.
注意力缺陷多动障碍(ADHD)与抑制冲动、多动和注意力不集中行为的困难有关。然而,尚无研究探讨在发育正常(TD)儿童和 ADHD 儿童中,是否存在一种不同的大脑活动模式先于抑制性错误。在健康成年人中,默认模式网络(一组在休息或内部关注状态下更活跃的大脑区域)的活动增加,预测了错误反应,表明注意力的瞬间丧失与抑制失败有关。
使用事件相关功能磁共振成像和 Go/No-Go 范式,探讨了 13 名 ADHD 儿童和 17 名 TD 对照组儿童在错误前的大脑活动。
与正确前的试验相比,TD 儿童在楔前叶/后扣带回皮质和旁海马回及额中回显示出激活。相比之下,ADHD 儿童表现出小脑、背外侧前额叶皮质(DLPFC)和基底节的激活。错误前与正确前对比的组间比较显示,与 TD 对照组相比,ADHD 儿童的小脑、DLPFC 和腹外侧前额叶皮质的活动更强。感兴趣区分析的结果证实,与 ADHD 儿童相比,TD 儿童的楔前叶/后扣带回皮质更活跃。
这些初步数据表明,ADHD 儿童和 TD 儿童在错误前的大脑激活模式存在差异。在 TD 儿童中,注意力瞬间丧失先于错误,而 ADHD 儿童的错误前活动可能由不同的回路介导,例如涉及反应选择和控制的回路。