Section for Experimental Neuropsychiatry, Department of Psychiatry and Psychotherapy, University of Freiburg Medical Center, Freiburg, Germany.
World J Biol Psychiatry. 2011 Jun;12(4):260-70. doi: 10.3109/15622975.2010.518624. Epub 2010 Sep 29.
Most structural imaging studies in ADHD have focused on prefronto-striatal circuits. However, findings remained inconsistent while recent reports point to the posterior parietal cortex as an additional target for research. Moreover, although adult ADHD clinically differs from the childhood presentation little is known about the structural correlates of ADHD in adults. The aim of this study was to clarify the involvement of prefronto-striatal and posterior parietal areas in adult ADHD.
Voxel-based morphometry of high resolution MRI scans was applied to analyze volumetric brain differences between 31 adult patients with ADHD and 31 control subjects.
The volume of prefrontal, striatal and parietal gray matter was normal. ADHD patients displayed a significant reduction of gray matter volume bilaterally in the early visual cortex (P<0.04).
The unexpected finding of visual cortex abnormalities might be related to impairments in early-stage, 'subexecutive" attentional mechanisms. The results support the notion that executive dysfunction may not be the dominant neurobiological characteristic of ADHD at least in adult patients. The visual cortex deserves more consideration as a potentially important site of dysfunction in adult and possibly childhood ADHD.
大多数注意力缺陷多动障碍（ADHD）的结构影像学研究都集中在前额-纹状体回路。然而，最近的报告指出，后顶叶皮层是另一个值得研究的目标，而这些发现仍然不一致。此外，尽管成人 ADHD 在临床上与儿童表现不同，但对于成人 ADHD 的结构相关性知之甚少。本研究旨在阐明前额-纹状体和顶后区域在成人 ADHD 中的参与情况。
我们应用高分辨率 MRI 扫描的基于体素的形态测量法来分析 31 名 ADHD 患者和 31 名对照受试者之间的脑容积差异。
前额叶、纹状体和顶叶灰质的体积正常。ADHD 患者双侧早期视觉皮层的灰质体积明显减少（P<0.04）。
视觉皮层异常的意外发现可能与早期“亚执行”注意力机制受损有关。结果支持这样一种观点，即执行功能障碍可能不是 ADHD 的主要神经生物学特征，至少在成年患者中不是。视觉皮层作为成人和可能儿童 ADHD 中功能障碍的潜在重要部位，值得进一步考虑。
