Department of Psychology, Temple University, Philadelphia, Pennsylvania, USA.
Department of Psychology and Neuroscience, Boston College, Chestnut Hill, Massachusetts, USA.
Hippocampus. 2020 Oct;30(10):1073-1080. doi: 10.1002/hipo.23216. Epub 2020 Jun 2.
Neuromodulatory regions that detect salience, such as amygdala and ventral tegmental area (VTA), have distinct effects on memory. Yet, questions remain about how these modulatory regions target subregions across the hippocampus and medial temporal lobe (MTL) cortex. Here, we sought to characterize how VTA and amygdala subregions (i.e., basolateral amygdala and central-medial amygdala) interact with hippocampus head, body, and tail, as well as cortical MTL areas of perirhinal cortex and parahippocampal cortex in a task-free state. To quantify these interactions, we used high-resolution resting state fMRI and characterized pair-wise, partial correlations across regions-of-interest. We found that basolateral amygdala showed greater functional coupling with hippocampus head, hippocampus tail, and perirhinal cortex when compared to either VTA or central-medial amygdala. Furthermore, the VTA showed greater functional coupling with hippocampus tail when compared to central-medial amygdala. There were no significant differences in functional coupling with hippocampus body and parahippocampal cortex. These results support a framework by which neuromodulatory regions do not indiscriminately influence all MTL subregions equally, but rather bias information processing to discrete MTL targets. These findings provide a more specified model of the intrinsic properties of systems underlying MTL neuromodulation. This emphasizes the need to consider heterogeneity both across and within neuromodulatory systems to better understand affective memory.
探测突显的神经调节区域，如杏仁核和腹侧被盖区（VTA），对记忆有明显的影响。然而，这些调节区域如何靶向海马体和内侧颞叶（MTL）皮质的亚区仍存在疑问。在这里，我们试图描述 VTA 和杏仁核亚区（即基底外侧杏仁核和中央-内侧杏仁核）如何在无任务状态下与海马体头部、体部和尾部以及皮质 MTL 区的边缘皮层和海马旁回相互作用。为了量化这些相互作用，我们使用高分辨率静息态 fMRI 并对感兴趣区域之间的成对部分相关进行了特征描述。我们发现，与 VTA 或中央-内侧杏仁核相比，基底外侧杏仁核与海马体头部、海马体尾部和边缘皮层的功能耦合更强。此外，与中央-内侧杏仁核相比，VTA 与海马体尾部的功能耦合更强。与海马体体部和海马旁回没有显著的功能耦合差异。这些结果支持了这样一种框架，即神经调节区域不会不加区别地同等影响所有 MTL 亚区，而是偏向于离散的 MTL 靶标进行信息处理。这些发现为 MTL 神经调节的内在特性提供了一个更具体的模型。这强调了需要考虑跨和在神经调节系统内的异质性，以更好地理解情感记忆。
