注意缺陷多动障碍儿童反应抑制功能的磁共振成像研究

Functional magnetic resonance imaging study of response inhibition in children with attention-deficit hyperactivity disorder

目的探讨注意缺陷多动障碍（ADHD）儿童执行高级反应抑制脑激活的模式和功能状态。方法对12例注意缺陷多动障碍儿童（ADHD组）和12名正常对照者（对照组）检测执行持续性操作测试任务（CPT）时的功能磁共振成像（fMRI）和行为学，并采集全脑血氧水平依赖对比的fMRI扫描数据。结果（1）行为学检测，ADHD组的击中数[（18．6±4．1）个]少于对照组[（22．8±1．8）个]，反应时间[（579±56）ms]长于正常对照组[（510±35）ms；均P〈0．01]，漏击数[（6．3±4．1）个]和错击数[（3．9±2．4）个]均多于对照组[（2．2±1．9）个和（1．9±1．0）个；P〈0．01-0．05]。（2）fMRI检测，ADHD组扣带前回、前额叶腹外侧、尾状核和小脑激活弱于对照组（P〈0．05，未校正，体素值〉20）。结论ADHD儿童反应抑制功能存在缺陷，其扣带前回、前额叶、基底节及小脑的功能低下。

Objective To study the brain activation and functional station when performing high-level response inhibition in children with attention-deficit hyperactivity disorder （ADHD）. Methods Event- related designed BOLD functional magnetic resonance imaging scan covering the whole brain was conducted in 12 right-handed children with ADHD and 12 normal children. The continuous performance test （CPT） was used as activation task. Results The ADHD children had lower hit numbers and longer reaction time than controls （P〈0.01）, with more missed（6.3±4. 1） and false alarms （3.9±2.4） than controls [（2.2±1.9） , （ 1.9±1.0） ; P 〈0.01-0. 05]. ADHD children showed decreased activations in anterior cingnlate cortex （dACC）, ventrolateral prefrontal cortex （VLPFC）, caudate nucleus and cerebellum （dACC） （ P〈0.05, uncorrected, voxel〉20）. Conclusion The children with ADHD have response inhibition impairment, and decreased activation in anterior cingulate cortex, prefrontal cortex, basal ganglia and cerebellum.