Lund University, Cognitive Science, Lund, SE-22100, Sweden.
Sci Rep. 2018 Mar 20;8(1):4871. doi: 10.1038/s41598-018-23265-x.
The processing of emotional signals usually causes an increase in pupil size, and this effect has been largely attributed to autonomic arousal prompted by the stimuli. Additionally, changes in pupil size were associated with decision making during non-emotional perceptual tasks. Therefore, in this study we investigated the relationship between pupil size fluctuations and the process of emotion recognition. Participants heard human nonverbal vocalizations (e.g., laughing, crying) and indicated the emotional state of the speakers as soon as they had identified it. The results showed that during emotion recognition, the time course of pupil response was driven by the decision-making process. In particular, peak pupil dilation betrayed the time of emotional selection. In addition, pupil response revealed properties of the decisions, such as the perceived emotional valence and the confidence in the assessment. Because pupil dilation (under isoluminance conditions) is almost exclusively promoted by norepinephrine (NE) release from the locus coeruleus (LC), the results suggest an important role of the LC-NE system during emotion processing.
情绪信号的处理通常会导致瞳孔大小的增加，而这种效应在很大程度上归因于刺激引起的自主唤醒。此外，瞳孔大小的变化与非情绪知觉任务中的决策有关。因此，在这项研究中，我们调查了瞳孔大小波动与情绪识别过程之间的关系。参与者听到人类的非言语发声（例如，笑声、哭声），并在识别出发声者的情绪状态后立即进行指示。结果表明，在情绪识别过程中，瞳孔反应的时间进程由决策过程驱动。具体来说，瞳孔扩张的峰值揭示了情绪选择的时间。此外，瞳孔反应揭示了决策的属性，例如感知的情绪效价和评估的信心。由于瞳孔扩张（在等光照条件下）几乎完全是由蓝斑核（LC）中的去甲肾上腺素（NE）释放所推动的，因此这些结果表明 LC-NE 系统在情绪处理过程中起着重要作用。
