Department of Neuroscience, CMU, University of Geneva, Geneva, Switzerland.
Neuroimage. 2011 Feb 1;54(3):2481-91. doi: 10.1016/j.neuroimage.2010.10.021. Epub 2010 Oct 16.
The functional properties of resting brain activity are poorly understood, but have generally been related to self-monitoring and introspective processes. Here we investigated how emotionally positive and negative information differentially influenced subsequent brain activity at rest. We acquired fMRI data in 15 participants during rest periods following fearful, joyful, and neutral movies. Several brain regions were more active during resting than during movie-watching, including posterior/anterior cingulate cortices (PCC, ACC), bilateral insula and inferior parietal lobules (IPL). Functional connectivity at different frequency bands was also assessed using a wavelet correlation approach and small-world network analysis. Resting activity in ACC and insula as well as their coupling were strongly enhanced by preceding emotions, while coupling between ventral-medial prefrontal cortex and amygdala was selectively reduced. These effects were more pronounced after fearful than joyful movies for higher frequency bands. Moreover, the initial suppression of resting activity in ACC and insula after emotional stimuli was followed by a gradual restoration over time. Emotions did not affect IPL average activity but increased its connectivity with other regions. These findings reveal specific neural circuits recruited during the recovery from emotional arousal and highlight the complex functional dynamics of default mode networks in emotionally salient contexts.
静息态大脑活动的功能特性尚未被充分理解，但通常与自我监控和内省过程有关。在这里，我们研究了情绪积极和消极信息如何在静息状态下对后续大脑活动产生不同影响。我们在 15 名参与者观看恐惧、快乐和中性电影后的静息期获取 fMRI 数据。与观看电影相比，几个大脑区域在静息状态下更为活跃，包括后/前扣带皮层（PCC、ACC）、双侧岛叶和下顶叶小叶（IPL）。我们还使用小波相关方法和小世界网络分析评估了不同频带的功能连接。ACC 和岛叶的静息活动及其耦合在前导情绪的作用下显著增强，而腹内侧前额叶皮层和杏仁核之间的耦合则选择性地减少。对于较高的频率带，观看恐惧电影后的这些效应比观看快乐电影更为明显。此外，情绪刺激后 ACC 和岛叶静息活动的初始抑制随后随着时间的推移逐渐恢复。情绪并没有影响 IPL 的平均活动，但增加了其与其他区域的连接性。这些发现揭示了在情绪唤醒后恢复过程中募集的特定神经回路，并强调了在情感相关情境中默认模式网络的复杂功能动态。
