University of Tübingen, Department of Psychiatry and Psychotherapy, Tübingen, Germany.
Queensland Institute of Medical Research, Brisbane, Australia; University of Magdeburg, Department of Psychiatry and Psychotherapy, Germany; Clinical Affective Neuroimaging Laboratory, Magdeburg, Germany; Leibniz Institute for Neurobiology, Magdeburg, Germany.
Neuroimage. 2019 Oct 15;200:414-424. doi: 10.1016/j.neuroimage.2019.06.041. Epub 2019 Jun 21.
Expectancy shapes our perception of impending events. Although such an interplay between cognitive and affective processes is often impaired in mental disorders, it is not well understood how top-down expectancy signals modulate future affect. We therefore track the information flow in the brain during cognitive and affective processing segregated in time using task-specific cross-correlations. Participants in two independent fMRI studies (N = 37 & N = 55) were instructed to imagine a situation with affective content as indicated by a cue, which was then followed by an emotional picture congruent with expectancy. To correct for intrinsic covariance of brain function, we calculate resting-state cross-correlations analogous to the task. First, using factorial modeling of delta cross-correlations (task-rest) of the first study, we find that the magnitude of expectancy signals in the anterior insula cortex (AIC) modulates the BOLD response to emotional pictures in the anterior cingulate and dorsomedial prefrontal cortex in opposite directions. Second, using hierarchical linear modeling of lagged connectivity, we demonstrate that expectancy signals in the AIC indeed foreshadow this opposing pattern in the prefrontal cortex. Third, we replicate the results in the second study using a higher temporal resolution, showing that our task-specific cross-correlation approach robustly uncovers the dynamics of information flow. We conclude that the AIC arbitrates the recruitment of distinct prefrontal networks during cued picture processing according to triggered expectations. Taken together, our study provides new insights into neuronal pathways channeling cognition and affect within well-defined brain networks. Better understanding of such dynamics could lead to new applications tracking aberrant information processing in mental disorders.
期待塑造了我们对即将发生事件的感知。尽管这种认知和情感过程之间的相互作用在精神障碍中经常受到损害，但人们尚不清楚自上而下的预期信号如何调节未来的情感。因此，我们使用特定于任务的交叉相关来追踪时间上分开的认知和情感处理过程中的信息流。在两个独立的 fMRI 研究（N=37 和 N=55）中，参与者被指示根据提示想象一种具有情感内容的情况，然后跟随一张与预期相符的情绪图片。为了纠正大脑功能的固有协方差，我们计算类似于任务的静息状态交叉相关。首先，使用第一研究中 delta 交叉相关（任务-静息）的因子建模，我们发现前岛叶皮层（AIC）中的预期信号幅度调节了前扣带和背内侧前额叶皮层对情绪图片的 BOLD 反应，方向相反。其次，使用滞后连接的层次线性建模，我们证明 AIC 中的预期信号确实预示了前额叶皮层中的这种相反模式。第三，我们在第二项研究中使用更高的时间分辨率复制了结果，表明我们的特定于任务的交叉相关方法可以稳健地揭示信息流的动态。我们得出结论，AIC 根据触发的预期来仲裁在提示图片处理过程中不同的前额叶网络的招募。总之，我们的研究为在定义明确的大脑网络中调节认知和情感的神经元途径提供了新的见解。更好地理解这种动态可能会导致在精神障碍中跟踪异常信息处理的新应用。
