Child Psychiatry Branch, National Institute of Mental Health, Bethesda, Maryland 20892, USA.
Biol Psychiatry. 2012 Aug 1;72(3):191-7. doi: 10.1016/j.biopsych.2012.01.031. Epub 2012 Mar 13.
Delineation of the cortical anomalies underpinning attention-deficit/hyperactivity disorder (ADHD) can powerfully inform pathophysiological models. We previously found that ADHD is characterized by a delayed maturation of prefrontal cortical thickness. We now ask if this extends to the maturation of cortical surface area and gyrification.
Two hundred thirty-four children with ADHD and 231 typically developing children participated in the study, with 837 neuroanatomic magnetic resonance images acquired longitudinally. We defined the developmental trajectories of cortical surfaces and gyrification and the sequence of cortical maturation, as indexed by the age at which each cortical vertex attained its peak surface area.
In both groups, the maturation of cortical surface area progressed in centripetal waves, both lateral (starting at the central sulcus and frontopolar regions, sweeping toward the mid and superior frontal gyrus) and medial (descending down the medial prefrontal cortex, toward the cingulate gyrus). However, the surface area developmental trajectory was delayed in ADHD. For the right prefrontal cortex, the median age by which 50% of cortical vertices attained peak area was 14.6 years (SE = .03) in ADHD, significantly later than in typically developing group at 12.7 years (SE = .03) [log-rank test χ(¹)² = 1300, p < .00001]. Similar, but less pronounced, delay was found in the left hemispheric lobes. There were no such diagnostic differences in the developmental trajectories of cortical gyrification.
The congruent delay in cortical thickness and surface area direct attention away from processes that selectively affect one cortical component toward mechanisms controlling the maturation of multiple cortical dimensions.
阐明 ADHD 皮质异常的特征可以为病理生理学模型提供有力信息。我们之前发现 ADHD 的前额皮质厚度成熟过程延迟。我们现在想问这是否会扩展到皮质表面积和脑回发育的成熟。
234 名 ADHD 儿童和 231 名典型发育儿童参与了这项研究，共获得 837 个神经解剖磁共振图像进行纵向研究。我们定义了皮质表面和脑回发育的轨迹，以及皮质成熟的顺序，以每个皮质顶点达到其表面积峰值的年龄来表示。
在两组中，皮质表面积的成熟过程呈向心性波进展，既有外侧（从中央沟和额极区域开始，向额中回和额上回方向推进）也有内侧（从内侧前额皮质向下，向扣带回方向推进）。然而，ADHD 的皮质表面积发育轨迹延迟。对于右前额皮质，达到 50%皮质顶点表面积峰值的中位数年龄在 ADHD 组为 14.6 岁（SE=0.03），显著晚于典型发育组的 12.7 岁（SE=0.03）[对数秩检验 χ²(1)=1300，p<0.00001]。在左半球也发现了类似但不太明显的延迟。皮质脑回发育轨迹没有这种诊断差异。
皮质厚度和表面积的一致延迟表明，这一现象并非选择性地影响单一皮质成分的过程，而是指向控制多个皮质维度成熟的机制。
