Li Fei, Li Bao-Juan, Hu De-Wen, Liu Jun, He Zhong, Zhou Shun-Ke
Mental Health Institute, Central South University, Changsha 410011, China.
Zhongguo Dang Dai Er Ke Za Zhi. 2010 Jan;12(1):24-8.
Impulsivity is one of the core symptoms of children with attention deficit hyperactivity disorder (ADHD). In order to understand the neuromechanism of the impulsive behaviors in ADHD children, this study investigated the specific functional areas of the brain by functional MRI.
The subjects consisted of 10 ADHD children with impulsivity, 7 ADHD children without impulsivity and 9 normal children. A functional MRI examination was performed when the subjects were instructed to finish GO and STOP tasks with the GO-STOP impulsivity paradigm. The MRI data during the two tasks of GO and STOP were averaged and the corresponding activation regions between groups were compared.
The data from the GO task revealed that the main activation regions of the normal children included frontal pole (superior frontal gyrus, middle frontal gyrus and medial frontal gyrus); the main activation regions of ADHD children without impulsivity were cerebellum (posterior lobe and anterior lobe bouton) and cingulated gyrus; those of ADHD children with impulsivity were medial globus pallidus and insula. The data from the STOP task showed that the main activation regions of normal children included superior frontal gyrus and middle frontal gyrus; those of ADHD children without impulsivity were middle frontal gyrus and cingulate gyrus; those of ADHD children with impulsivity were uncus and putamen. The activation regions of ADHD children with impulsivity were much fewer than the other two groups.
The behavior of impulsivity-control involves a number of specific functional areas in the cerebral cortex. Compared with normal children, ADHD children without impulsivity have weaker brain function and brain activation, and ADHD children with impulsivity demonstrate much fewer brain activation regions, worse brain function and little awareness of the cerebral cortex.
冲动性是注意缺陷多动障碍（ADHD）患儿的核心症状之一。为了解ADHD患儿冲动行为的神经机制，本研究通过功能磁共振成像研究大脑的特定功能区域。
研究对象包括10名有冲动性的ADHD患儿、7名无冲动性的ADHD患儿和9名正常儿童。当受试者按照GO-STOP冲动范式完成GO和STOP任务时，进行功能磁共振成像检查。对GO和STOP两项任务期间的磁共振成像数据进行平均，并比较各组之间相应的激活区域。
GO任务的数据显示，正常儿童的主要激活区域包括额极（额上回、额中回和额内侧回）；无冲动性的ADHD患儿的主要激活区域是小脑（后叶和前叶小结）和扣带回；有冲动性的ADHD患儿的主要激活区域是苍白球内侧部和脑岛。STOP任务的数据显示，正常儿童的主要激活区域包括额上回和额中回；无冲动性的ADHD患儿的主要激活区域是额中回和扣带回；有冲动性的ADHD患儿的主要激活区域是钩回和壳核。有冲动性的ADHD患儿的激活区域比其他两组少得多。
冲动控制行为涉及大脑皮层的多个特定功能区域。与正常儿童相比，无冲动性的ADHD患儿脑功能和脑激活较弱，有冲动性的ADHD患儿脑激活区域少得多，脑功能较差，大脑皮层的意识较弱。
