Emotional stimuli and motor conversion disorder
Emotional stimuli and motor conversion disorder
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DOI：
10.1093/brain/awq054
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发表时间：
2010-05-01
期刊：
影响因子：
14.5
通讯作者：
Hallett, Mark
中科院分区：
文献类型：
--
作者：
Voon, Valerie;Brezing, Christina;Hallett, Mark
转换障碍的特征是与潜在心理问题相关的神经学体征和症状。杏仁核活动的情感刺激是很好的特点，在健康志愿者与更大的杏仁核活动的负面和积极的刺激相对于中性刺激，和更大的活动，负面相对于积极的刺激。我们通过评估杏仁核对情感刺激的活性来研究转换障碍和情感之间的关系。我们进行了一项功能性磁共振成像研究，使用块设计附带的情感任务与恐惧，快乐和中性的面孔刺激，并比较了16例转换障碍患者和16名年龄和性别匹配的健康志愿者之间的效价对比。转换障碍的患者有积极的运动，如震颤，肌张力障碍或步态异常。我们还评估了杏仁核和与运动准备相关的区域之间的功能连接。观察到一组情感效价相互作用。事后分析显示，虽然健康志愿者有更大的右杏仁核活动，恐惧与中性相比，快乐与中性的预期，有转换障碍患者没有效价差异。未观察到组间差异。时程分析还显示，与健康志愿者相比，转换障碍患者对快乐刺激的右侧杏仁核活动更大（t = 2.96，P = 0.006）（具有恐惧刺激的趋势，t = 1.81，P = 0.08），即使在控制抑郁和焦虑症状时，杏仁核习惯性受损的模式也提示。使用心理生理学的相互作用分析，转换障碍患者有更大的功能连接的右侧杏仁核和右侧辅助运动区在恐惧与中性，快乐与中性的“刺激”与健康志愿者相比。这些结果与格兰杰因果关系模型分析结果一致，表明从右侧杏仁核到右侧辅助运动区对快乐刺激有方向性影响（P < 0.05），对恐惧刺激有类似的趋势（P = 0.07）。我们的数据提供了一个潜在的神经机制，可以解释为什么心理或生理压力可以触发或加剧某些患者的转换障碍症状。在觉醒状态下，边缘系统区域影响运动准备区域的更大功能连接可能是运动转换症状的病理生理学基础。
Conversion disorder is characterized by neurological signs and symptoms related to an underlying psychological issue. Amygdala activity to affective stimuli is well characterized in healthy volunteers with greater amygdala activity to both negative and positive stimuli relative to neutral stimuli, and greater activity to negative relative to positive stimuli. We investigated the relationship between conversion disorder and affect by assessing amygdala activity to affective stimuli. We conducted a functional magnetic resonance imaging study using a block design incidental affective task with fearful, happy and neutral face stimuli and compared valence contrasts between 16 patients with conversion disorder and 16 age- and gender-matched healthy volunteers. The patients with conversion disorder had positive movements such as tremor, dystonia or gait abnormalities. We also assessed functional connectivity between the amygdala and regions associated with motor preparation. A group by affect valence interaction was observed. Post hoc analyses revealed that whereas healthy volunteers had greater right amygdala activity to fearful versus neutral compared with happy versus neutral as expected, there were no valence differences in patients with conversion disorder. There were no group differences observed. The time course analysis also revealed greater right amygdala activity in patients with conversion disorder for happy stimuli (t = 2.96, P = 0.006) (with a trend for fearful stimuli, t = 1.81, P = 0.08) compared with healthy volunteers, with a pattern suggestive of impaired amygdala habituation even when controlling for depressive and anxiety symptoms. Using psychophysiological interaction analysis, patients with conversion disorder had greater functional connectivity between the right amygdala and the right supplementary motor area during both fearful versus neutral, and happy versus neutral 'stimuli' compared with healthy volunteers. These results were confirmed with Granger Causality Modelling analysis indicating a directional influence from the right amygdala to the right supplementary motor area to happy stimuli (P < 0.05) with a similar trend observed to fearful stimuli (P = 0.07). Our data provide a potential neural mechanism that may explain why psychological or physiological stressors can trigger or exacerbate conversion disorder symptoms in some patients. Greater functional connectivity of limbic regions influencing motor preparatory regions during states of arousal may underlie the pathophysiology of motor conversion symptoms.