Behavioral Research Unit, Department of Pediatrics, Alberta Children's Hospital, University of Calgary, 2888 Shaganappi Trail NW, Calgary, AB T3B 6A8, Canada.
J Neural Transm (Vienna). 2010 May;117(5):655-62. doi: 10.1007/s00702-010-0374-y. Epub 2010 Feb 16.
Inhibition problems in attention deficit hyperactivity disorder (ADHD) are sensitive to stimulus event rate. This pilot study explores the neural basis of this increased susceptibility to event rate in ADHD. Event-related functional magnetic resonance imaging was used in conjunction with the administration of a fast (1.5 s) and a slow (7 s) Go/No-Go task. Brain activity patterns and reaction times of ten young male adults with ADHD (two of whom were in partial remission) and ten healthy male controls were compared. The ADHD group responded slower than controls with greater variability but with similar number of errors. Accurate response inhibition in the ADHD group in the slow condition was associated with widespread fronto-striatal activation, including the thalamus. For correct Go trials only, the ADHD group compared with controls showed substantial under-activation in the slow condition. The observed abnormal brain activation in the slow condition in adults with ADHD supports a fronto-striatal etiology, and underlines a presumed activation regulation deficit. Larger sample sizes to further validate these preliminary findings are needed.
注意缺陷多动障碍（ADHD）中的抑制问题对刺激事件率敏感。这项初步研究探索了 ADHD 患者对事件率增加的敏感性的神经基础。事件相关功能磁共振成像与快速（1.5 秒）和慢速（7 秒）Go/No-Go 任务一起使用。比较了十名年轻男性 ADHD 患者（其中两名处于部分缓解期）和十名健康男性对照者的大脑活动模式和反应时间。ADHD 组的反应速度比对照组慢，变异性更大，但错误数相同。在慢速条件下，ADHD 组准确的反应抑制与广泛的额纹状体激活有关，包括丘脑。仅对于正确的 Go 试验，与对照组相比，ADHD 组在慢速条件下显示出明显的激活不足。在患有 ADHD 的成年人中观察到的慢速条件下的异常大脑激活支持额纹状体病因，并强调了假定的激活调节缺陷。需要更大的样本量来进一步验证这些初步发现。
