Daselaar Sander M, Rice Heather J, Greenberg Daniel L, Cabeza Roberto, LaBar Kevin S, Rubin David C
Department of Psychology and Neuroscience, Duke University, Durham, NC 27708, USA.
Cereb Cortex. 2008 Jan;18(1):217-29. doi: 10.1093/cercor/bhm048. Epub 2007 Jun 4.
We sought to map the time course of autobiographical memory retrieval, including brain regions that mediate phenomenological experiences of reliving and emotional intensity. Participants recalled personal memories to auditory word cues during event-related functional magnetic resonance imaging (fMRI). Participants pressed a button when a memory was accessed, maintained and elaborated the memory, and then gave subjective ratings of emotion and reliving. A novel fMRI approach based on timing differences capitalized on the protracted reconstructive process of autobiographical memory to segregate brain areas contributing to initial access and later elaboration and maintenance of episodic memories. The initial period engaged hippocampal, retrosplenial, and medial and right prefrontal activity, whereas the later period recruited visual, precuneus, and left prefrontal activity. Emotional intensity ratings were correlated with activity in several regions, including the amygdala and the hippocampus during the initial period. Reliving ratings were correlated with activity in visual cortex and ventromedial and inferior prefrontal regions during the later period. Frontopolar cortex was the only brain region sensitive to emotional intensity across both periods. Results were confirmed by time-locked averages of the fMRI signal. The findings indicate dynamic recruitment of emotion-, memory-, and sensory-related brain regions during remembering and their dissociable contributions to phenomenological features of the memories.
我们试图描绘自传体记忆提取的时间进程，包括介导重温现象学体验和情感强度的脑区。在事件相关功能磁共振成像（fMRI）期间，参与者根据听觉单词线索回忆个人记忆。当回忆被提取、维持和细化时，参与者按下按钮，然后对情感和重温进行主观评分。一种基于时间差异的新型fMRI方法利用了自传体记忆漫长的重建过程，以区分对情景记忆的初始提取以及后期细化和维持有贡献的脑区。初始阶段涉及海马体、压后皮质以及内侧和右侧前额叶活动，而后期则募集视觉、楔前叶和左侧前额叶活动。情感强度评分与多个脑区的活动相关，包括初始阶段的杏仁核和海马体。重温评分与后期视觉皮层、腹内侧和前额叶下部区域的活动相关。额极皮质是两个阶段中唯一对情感强度敏感的脑区。结果通过fMRI信号的锁时平均值得到证实。这些发现表明，在记忆过程中，与情感、记忆和感觉相关的脑区会动态募集，并且它们对记忆的现象学特征有可分离的贡献。
