Dept. of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany.
Dept. of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany.
Neuroimage. 2018 Sep;178:423-434. doi: 10.1016/j.neuroimage.2018.05.059. Epub 2018 May 26.
Human faces are among the most salient visual stimuli and act both as socially and emotionally relevant signals. Faces and especially faces with emotional expression receive prioritized processing in the human brain and activate a distributed network of brain areas reflected, e.g., in enhanced oscillatory neuronal activity. However, an inconsistent picture emerged so far regarding neuronal oscillatory activity across different frequency-bands modulated by emotionally and socially relevant stimuli. The individual level of anxiety among healthy populations might be one explanation for these inconsistent findings. Therefore, we tested the hypothesis whether oscillatory neuronal activity is associated with individual anxiety levels during perception of faces with neutral and fearful facial expressions. We recorded neuronal activity using magnetoencephalography (MEG) in 27 healthy participants and determined their individual state anxiety levels. Images of human faces with neutral and fearful expressions, and physically matched visual control stimuli were presented while participants performed a simple color detection task. Spectral analyses revealed that face processing and in particular processing of fearful faces was characterized by enhanced neuronal activity in the theta- and gamma-band and decreased activity in the beta-band in early visual cortex and the fusiform gyrus (FFG). Moreover, the individuals' state anxiety levels correlated positively with the gamma-band response and negatively with the beta response in the FFG and the amygdala. Our results suggest that oscillatory neuronal activity plays an important role in affective face processing and is dependent on the individual level of state anxiety. Our work provides new insights on the role of oscillatory neuronal activity underlying processing of faces.
人脸是最显著的视觉刺激之一，既是社交相关的，也是情感相关的信号。人脸，尤其是带有表情的人脸，在人类大脑中受到优先处理，并激活大脑中分布的区域网络，例如增强的振荡神经元活动。然而，到目前为止，关于情绪和社交相关刺激调制的不同频带的神经元振荡活动的不一致的情况出现了。健康人群中的个体焦虑水平可能是这些不一致发现的一个解释。因此，我们测试了这样一个假设，即在感知具有中性和恐惧面部表情的面孔时，神经元振荡活动是否与个体的焦虑水平有关。我们使用脑磁图（MEG）在 27 名健康参与者中记录了神经元活动，并确定了他们的个体状态焦虑水平。呈现具有中性和恐惧表情的人类面孔的图像以及物理匹配的视觉控制刺激，而参与者执行简单的颜色检测任务。频谱分析表明，面孔处理，特别是恐惧面孔的处理，在早期视觉皮层和梭状回（FFG）中表现为theta 和 gamma 波段的神经元活动增强，beta 波段的活动减少。此外，个体的状态焦虑水平与 FFG 和杏仁核中的 gamma 波段反应呈正相关，与 beta 反应呈负相关。我们的结果表明，振荡神经元活动在情感面孔处理中起着重要作用，并且取决于个体的状态焦虑水平。我们的工作为处理面孔的振荡神经元活动的作用提供了新的见解。
