Blum Austin W, Chamberlain Samuel R, Harries Michael D, Odlaug Brian L, Redden Sarah A, Grant Jon E
From the Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago (AWB, MDH, SAR, JEG); the Department of Psychiatry, University of Cambridge, United Kingdom (SRC); Cambridge and Peterborough NHS Foundation Trust, Cambridge, United Kingdom (SRC); the Department of Public Health, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (BLO); and H. Lundbeck A/S, Valby, Denmark (BLO).
J Neuropsychiatry Clin Neurosci. 2018 Summer;30(3):236-241. doi: 10.1176/appi.neuropsych.17050090. Epub 2018 Apr 24.
Excoriation (skin-picking) disorder (SPD) has similarities to obsessive-compulsive disorder (OCD) and is included within the obsessive-compulsive and related disorders (OCRD) diagnostic class in DSM-5. Separate neuroimaging and neurocognitive studies suggest that people affected by SPD find it difficult to inhibit dominant motor responses due to a failure of "top-down" control mechanisms. No study has examined the neural correlates of SPD in participants with varying degrees of impulsive motor behavior. This study correlated cortical thickness and volumes of selected subcortical structures with stop-signal task performance in participants with SPD (N=15) and in healthy control subjects (N=8). All participants were free from current psychiatric comorbidity, including OCD. In volunteers with SPD, longer stop-signal reaction times were correlated with cortical thinning in the right insula and right-inferior parietal lobe and with increased cortical thickness in the left-lateral occipital lobe, though these findings did not withstand correction for multiple comparisons. There were no significant correlations between cortical thickness in these three structures and stop-signal reaction times in the control group. This study suggests that structural abnormalities in the insular cortex and parietal and occipital regions may play a role in the pathophysiology of SPD. Further neuroimaging research is needed to understand the neurobiology of SPD and its relationship with other putative OCRDs.
皮肤搔抓障碍（SPD）与强迫症（OCD）有相似之处，在《精神疾病诊断与统计手册》第五版（DSM - 5）中被纳入强迫及相关障碍（OCRD）诊断类别。单独的神经影像学和神经认知研究表明，受SPD影响的人由于“自上而下”控制机制失效，难以抑制主导运动反应。尚无研究考察不同程度冲动运动行为的参与者中SPD的神经关联。本研究将皮质厚度和选定的皮质下结构体积与SPD参与者（N = 15）和健康对照者（N = 8）的停止信号任务表现进行关联分析。所有参与者目前均无包括OCD在内的精神疾病共病。在患有SPD的志愿者中，较长的停止信号反应时间与右侧岛叶和右下顶叶的皮质变薄以及左侧枕叶皮质厚度增加相关，尽管这些发现未通过多重比较校正。在对照组中，这三个结构的皮质厚度与停止信号反应时间之间无显著相关性。本研究表明，岛叶皮质以及顶叶和枕叶区域的结构异常可能在SPD的病理生理学中起作用。需要进一步开展神经影像学研究以了解SPD的神经生物学及其与其他假定的OCRD的关系。
