Mood and Anxiety Disorders Program at the National Institute of Mental Health in Bethesda, MD, USA.
J Am Acad Child Adolesc Psychiatry. 2010 Sep;49(9):944-53. doi: 10.1016/j.jaac.2010.05.006. Epub 2010 Jun 29.
Deficits in cognitive flexibility and response inhibition have been linked to perturbations in cortico-striatal-thalamic circuitry in adult obsessive-compulsive disorder (OCD). Although similar cognitive deficits have been identified in pediatric OCD, few neuroimaging studies have been conducted to examine its neural correlates in the developing brain. In this study, we tested hypotheses regarding group differences in the behavioral and neural correlates of cognitive flexibility in a pediatric OCD and a healthy comparison (HC) sample.
In this functional magnetic resonance imaging (fMRI) study, a pediatric sample of 10- to 17-year-old subjects, 15 with OCD and 20 HC, completed a set-shifting task. The task, requiring an extradimensional shift to identify a target, examines cognitive flexibility. Within each block, the dimension (color or shape) that identified the target either alternated (i.e., mixed) or remained unchanged (i.e., repeated).
Compared with the HC group, the OCD group tended to be slower to respond to trials within mixed blocks. Compared with the HC group, the OCD group exhibited less left inferior frontal gyrus/BA47 activation in the set-shifting contrast (i.e., HC > OCD, mixed versus repeated); only the HC group exhibited significant activation in this region. The correlation between set shifting-induced right caudate activation and shift cost (i.e., reaction time differential in response to mixed versus repeated trials) was significantly different between HC and OCD groups, in that we found a positive correlation in HC and a negative correlation in OCD.
In pediatric OCD, less fronto-striatal activation may explain previously identified deficits in shifting cognitive sets.
认知灵活性和反应抑制的缺陷与成年强迫症（OCD）皮质-纹状体-丘脑回路的扰动有关。尽管在儿科 OCD 中也发现了类似的认知缺陷，但很少有神经影像学研究来检查其在发育中的大脑中的神经相关性。在这项研究中，我们测试了关于儿科 OCD 和健康对照组（HC）样本中认知灵活性的行为和神经相关性的组间差异的假设。
在这项功能磁共振成像（fMRI）研究中，我们对 10 至 17 岁的儿科样本进行了研究，其中包括 15 名 OCD 患者和 20 名 HC，完成了一系列转换任务。该任务要求进行额外的维度转换以识别目标，检查认知灵活性。在每个块中，识别目标的维度（颜色或形状）要么交替（即混合），要么保持不变（即重复）。
与 HC 组相比，OCD 组在混合块内的反应速度较慢。与 HC 组相比，OCD 组在转换对比中左额下回/BA47 的激活较少（即 HC > OCD，混合对重复）；只有 HC 组在该区域表现出显著的激活。设定转换诱导的右侧尾状核激活与转换成本（即对混合与重复试验的反应时间差异）之间的相关性在 HC 和 OCD 组之间存在显著差异，因为我们在 HC 组中发现了正相关，而在 OCD 组中发现了负相关。
在儿科 OCD 中，额纹状体的激活减少可能解释了先前确定的认知灵活性缺陷。
