Fornito Alex, Wood Stephen J, Whittle Sarah, Fuller Jack, Adamson Chris, Saling Michael M, Velakoulis Dennis, Pantelis Christos, Yücel Murat
Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Melbourne, Australia.
Hum Brain Mapp. 2008 Feb;29(2):222-36. doi: 10.1002/hbm.20381.
The structural and functional consequences of interindividual variations in cortical morphology are poorly understood. In this study, we examined the relationship between one well-characterized variation of the medial frontal lobes, variability of the paracingulate sulcus (PCS), and grey matter volume, cortical thickness, surface area, and sulcal depth of the adjacent anterior cingulate cortex (ACC) and paracingulate cortex (PaC). Seventy-seven healthy individuals were assigned to one of four groups depending on PCS incidence in both hemispheres: left-present, right-absent; left-absent, right-present; both absent; or both present. Comparing these groups on each measure yielded four primary findings: (1) The presence of a PCS was associated with increased PaC and decreased ACC grey matter volume in the hemisphere in which it was apparent, with an almost identical pattern being observed for surface area; (2) there was a more complex relationship between PCS variability and regional thickness, such that a PCS in the left hemisphere was associated with increased left PaC and right ACC thickness, with no comparable effects being observed for the presence of a right PCS; (3) the depths of all major left hemisphere sulci in the region were strongly positively correlated, whereas no such associations were apparent in the right hemisphere; and (4) a leftward asymmetry in PaC thickness was specifically associated with better performance on a test of spatial working memory ability. These results provide evidence for a complex interhemispheric relationship between sulcal variability and cortical morphometry, and indicate that such relationships may be important for understanding individual differences in cognitive abilities.
目前人们对皮质形态个体间差异所产生的结构和功能后果知之甚少。在本研究中，我们探讨了内侧额叶一个特征明确的变异——扣带旁沟（PCS）的变异性，与相邻前扣带回皮质（ACC）和扣带旁皮质（PaC）的灰质体积、皮质厚度、表面积及沟深度之间的关系。根据双侧半球的PCS发生率，77名健康个体被分为四组之一：左侧存在、右侧缺失；左侧缺失、右侧存在；双侧均缺失；或双侧均存在。对这些组在各项指标上进行比较得出了四项主要发现：（1）PCS的存在与该侧半球PaC增加及ACC灰质体积减少相关，表面积也呈现出几乎相同的模式；（2）PCS变异性与区域厚度之间存在更复杂的关系，即左半球的PCS与左侧PaC和右侧ACC厚度增加相关，而右侧PCS的存在未观察到类似影响；（3）该区域左侧半球所有主要脑沟的深度呈强正相关，而右侧半球未出现这种关联；（4）PaC厚度的左侧不对称性与空间工作记忆能力测试中的更好表现特别相关。这些结果为脑沟变异性与皮质形态测量之间复杂的半球间关系提供了证据，并表明这种关系可能对理解认知能力的个体差异很重要。
