Emotional expressions, but not social context, modulate attention during a discrimination task

Investigating social context effects and emotional modulation of attention in a laboratory setting is challenging. Electroencephalography (EEG) requires a controlled setting to avoid confounds, which goes against the nature of social interaction and emotional processing in real life. To bridge this gap, we developed a new paradigm to investigate the effects of social context and emotional expressions on attention in a laboratory setting. We co-registered eye-tracking and EEG to assess gaze behavior and brain activity while participants performed a discrimination task followed by feedback. Video clips of one second in which a confederate displayed either positive, neutral or negative expressions were presented as feedback to the discrimination task. Participants’ belief was manipulated by telling them that the videos were selected either by the computer (non-social condition) or by the experimenter in the adjacent room that observed them via videochat (social condition). We found that emotional expressions modulated late attention processing in the brain (EPN and LPC), but neither early processing (P1) nor saccade latency. Social context did not influence any of the variables studied. We conclude this new paradigm serves as a stepping stone to the development of new paradigms to study social interaction within EEG experiments.

在实验室环境中研究社会背景效应及情绪对注意力的调节颇具挑战性。脑电图（Electroencephalography，EEG）需要受控环境以避免混淆变量，而这与现实生活中社会互动及情绪加工的本质相悖。为填补这一空白，我们开发了一种新范式，旨在实验室环境中探究社会背景及情绪表达对注意力的影响。我们联合记录眼动追踪（eye-tracking）数据与EEG信号，以评估参与者完成辨别任务并接收反馈期间的注视行为及大脑活动。时长1秒的视频片段被用作辨别任务的反馈，片段中同盟者（confederate）表现出积极、中性或消极的表情。我们通过操纵参与者的信念，告知他们视频要么由计算机（非社会条件，non-social condition）选择，要么由通过视频聊天观察他们的邻室实验者（社会条件，social condition）选择。研究发现，情绪表达调节大脑的晚期注意力加工（EPN和LPC），但对早期加工（P1）或眼跳潜伏期（saccade latency）均无影响；社会背景对所研究的任何变量均无显著作用。我们得出结论，该新范式为EEG实验中社会互动研究的新范式开发提供了重要基础。