National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland, USA.
Biol Psychiatry. 2012 Mar 1;71(5):443-50. doi: 10.1016/j.biopsych.2011.11.003. Epub 2011 Dec 6.
Attention-deficit/hyperactivity disorder (ADHD) is typically characterized by symptoms of inattention and hyperactivity/impulsivity, but there is increased recognition of a motivation deficit too. This neuropathology may reflect dysfunction of both attention and reward-motivation networks.
To test this hypothesis, we compared the functional connectivity density between 247 ADHD and 304 typically developing control children from a public magnetic resonance imaging database. We quantified short- and long-range functional connectivity density in the brain using an ultrafast data-driven approach.
Children with ADHD had lower connectivity (short- and long-range) in regions of the dorsal attention (superior parietal cortex) and default-mode (precuneus) networks and in cerebellum and higher connectivity (short-range) in reward-motivation regions (ventral striatum and orbitofrontal cortex) than control subjects. In ADHD children, the orbitofrontal cortex (region involved in salience attribution) had higher connectivity with reward-motivation regions (striatum and anterior cingulate) and lower connectivity with superior parietal cortex (region involved in attention processing).
The enhanced connectivity within reward-motivation regions and their decreased connectivity with regions from the default-mode and dorsal attention networks suggest impaired interactions between control and reward pathways in ADHD that might underlie attention and motivation deficits in ADHD.
注意力缺陷多动障碍（ADHD）通常以注意力不集中和多动/冲动的症状为特征，但也越来越认识到存在动机缺陷。这种神经病理学可能反映了注意力和奖励动机网络的功能障碍。
为了验证这一假设，我们比较了来自公共磁共振成像数据库的 247 名 ADHD 儿童和 304 名典型发育对照儿童之间的功能连接密度。我们使用超快数据驱动方法量化了大脑中的短程和长程功能连接密度。
与对照组相比，ADHD 儿童的背侧注意（顶下皮质）和默认模式（楔前叶）网络以及小脑的连接（短程和长程）较低，而奖励动机区域（腹侧纹状体和眶额皮层）的连接（短程）较高。在 ADHD 儿童中，眶额皮层（参与突显归因的区域）与奖励动机区域（纹状体和前扣带皮层）的连接较高，与顶下皮质（参与注意力处理的区域）的连接较低。
奖励动机区域内的连接增强以及与默认模式和背侧注意网络区域的连接减少表明 ADHD 中控制和奖励途径之间的相互作用受损，这可能是 ADHD 中注意力和动机缺陷的基础。
