Harvey Philippe-Olivier, Fossati Philippe, Lepage Martin
McGill University, Québec, Canada.
J Cogn Neurosci. 2007 Feb;19(2):351-62. doi: 10.1162/jocn.2007.19.2.351.
It is unclear whether the involvement of the medial prefrontal cortex (mPFC) during encoding is restricted to the evaluative processing of to-be-encoded stimuli or if it is instead actively engaged during memory formation. The difficulty of assessing the contribution of the mPFC to encoding based on previous neuroimaging studies partly arises from the use of several types of stimuli, such as emotional or social ones. These different types of stimulus content could differently modulate mPFC activity during memory formation and thus partly explain the variable contribution of this region to encoding. Using emotional/neutral and social/nonsocial pictures, we conducted an event-related functional magnetic resonance imaging study using a subsequent memory paradigm as the main analytical strategy. We observed that the brain activity in the dorsal and orbital mPFC is significantly and specifically predictive of the successful encoding of social compared with nonsocial pictures. In contrast, the activity in the amygdala specifically predicts the successful encoding of emotional compared with neutral pictures. The modulation of the mPFC by social information in a memory encoding context could be associated with the initiation of self-referential processes whose contribution is to enhance memory formation.
目前尚不清楚内侧前额叶皮质（mPFC）在编码过程中的参与是否仅限于对即将被编码刺激的评估处理，或者它是否在记忆形成过程中积极参与。基于先前的神经影像学研究评估mPFC对编码贡献的困难部分源于使用了多种类型的刺激，如情感或社会刺激。这些不同类型的刺激内容在记忆形成过程中可能会以不同方式调节mPFC的活动，从而部分解释了该区域对编码的可变贡献。我们使用情感/中性和社会/非社会图片，采用后续记忆范式作为主要分析策略，进行了一项事件相关功能磁共振成像研究。我们观察到，与非社会图片相比，背侧和眶额mPFC的大脑活动显著且特异性地预测了社会图片的成功编码。相反，与中性图片相比，杏仁核的活动特异性地预测了情感图片的成功编码。在记忆编码背景下，社会信息对mPFC的调节可能与自我参照过程的启动有关，其作用是增强记忆形成。
