CNRS USR 3246, Pitié-Salpêtrière Hospital, 47 boulevard de l'Hôpital, 75013 Paris, France.
Soc Cogn Affect Neurosci. 2011 Sep;6(4):426-33. doi: 10.1093/scan/nsq049. Epub 2010 Jun 2.
The neural bases of the association between negative affectivity and self-focus remain unknown in healthy subjects. Building on the role of the cortical midline structures (CMS) in self-referential processing, we hypothesized that negative affectivity in healthy subjects would be associated with an increased activation of the CMS during self-referential processing. We presented positive and negative pictures to 45 healthy subjects during fMRI and asked them to judge whether the pictures were related to themselves or not (self condition), or whether the pictures were positive or negative (general condition). Negative affectivity was measured by the level of harm avoidance (HA) with the Temperament and Character Inventory. Self-referential processing activated the CMS, including the dorsal and ventral medial prefrontal cortex (MPFC) and the posterior cingulate cortex (PCC). A higher HA score was associated with a greater activation of the dorsal MPFC and PCC during self-referential processing, this greater activation being more pronounced for negative pictures in the dorsal MPFC. This increased activation of the CMS may embody the association between negative affectivity and self-focus in healthy subjects, as previously observed in major depression. Within the CMS, the dorsal MPFC may play a key role in negative affectivity, integrating an increased attention to negative stimuli with an increased attention to the self.
在健康受试者中，负性情感与自我关注之间的关联的神经基础尚不清楚。基于皮质中线结构（CMS）在自我参照处理中的作用，我们假设健康受试者的负性情感与自我参照处理期间 CMS 的激活增加有关。我们在 fMRI 期间向 45 名健康受试者呈现正性和负性图片，并要求他们判断图片是否与自己有关（自我条件），或者图片是正性的还是负性的（一般条件）。负性情感通过特质和性格问卷中的回避度量来测量。自我参照处理激活了 CMS，包括背侧和腹侧内侧前额叶皮质（MPFC）和后扣带皮层（PCC）。较高的 HA 评分与自我参照处理期间背侧 MPFC 和 PCC 的激活增加有关，在背侧 MPFC 中，这种更大的激活对于负性图片更为明显。CMS 的这种激活增加可能体现了健康受试者中负性情感与自我关注之间的关联，正如在重度抑郁症中观察到的那样。在 CMS 内部，背侧 MPFC 可能在负性情感中发挥关键作用，将对负性刺激的注意力增加与对自我的注意力增加结合起来。
