This study investigated the neural correlates of the judgement of auditory and visual ambiguous threat-related information, and the influence of state anxiety on this process. Healthy subjects were scanned using a fast, high-resolution functional magnetic resonance imaging (fMRI) multiband sequence while they performed a two-alternative forced-choice emotion judgement task on faces and vocal utterances conveying explicit anger or fear, as well as ambiguous ones. Critically, the latter was specific to each subject, obtained through a morphing procedure and selected prior to scanning following a perceptual decision-making task. Behavioural results confirmed a greater task-difficulty for subject-specific ambiguous stimuli and also revealed a judgement bias for visual fear, and, to a lesser extent, for auditory anger. Imaging results showed increased activity in regions of the salience and frontoparietal control networks (FPCNs) and deactivation in areas of the default mode network for ambiguous, relative to explicit, expressions. In contrast, the right amygdala (AMG) responded more strongly to explicit stimuli. Interestingly, its response to the same ambiguous stimulus depended on the subjective judgement of the expression. Finally, we found that behavioural and neural differences between ambiguous and explicit expressions decreased as a function of state anxiety scores. Taken together, our results show that behavioural and brain responses to emotional expressions are determined not only by emotional clarity but also modality and the subjects' subjective perception of the emotion expressed, and that some of these responses are modulated by state anxiety levels.

中文翻译：

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模糊视觉和听觉威胁相关表达评估的个体差异

本研究调查了听觉和视觉模糊威胁相关信息判断的神经相关性，以及状态焦虑对此过程的影响。使用快速、高分辨率功能磁共振成像（fMRI）多波段序列对健康受试者进行扫描，同时对表达明确愤怒或恐惧以及模糊的面孔和声音进行两种选择的强制选择情绪判断任务。至关重要的是，后者是针对每个受试者的，通过变形程序获得，并在执行感知决策任务后进行扫描之前进行选择。行为结果证实了针对特定对象的模糊刺激的任务难度更大，并且还揭示了对视觉恐惧的判断偏差，以及在较小程度上对听觉愤怒的判断偏差。成像结果显示，相对于明确的表达，显着性和额顶控制网络（FPCN）区域的活动增加，而默认模式网络区域的活动则失活。相比之下，右侧杏仁核（AMG）对明确的刺激反应更强烈。有趣的是，它对同样模糊刺激的反应取决于表达的主观判断。最后，我们发现模糊表达和明确表达之间的行为和神经差异随着状态焦虑分数的变化而减少。总而言之，我们的结果表明，对情绪表达的行为和大脑反应不仅取决于情绪的清晰度，还取决于情态和受试者对表达的情绪的主观感知，并且其中一些反应受到状态焦虑水平的调节。