Department of Psychology, University of Konstanz, Konstanz, Germany.
Psychophysiology. 2019 Aug;56(8):e13386. doi: 10.1111/psyp.13386. Epub 2019 Apr 26.
EEG power analysis is firmly established in the cognitive domain. This contrasts with emotional stimulus processing, which thus far has yielded a complex and ambiguous pattern of findings. To further advance understanding, the present study examined emotional stimulus processing in the context of task variations and baseline activity, which included several manipulation checks as well as internal replication of findings across conditions. Participants (N = 16) viewed erotic and romantic pictures, differing in stimulus arousal. Pictures were presented briefly (120 ms), and intertrial interval was systematically varied (~1 vs. ~8 s). In one condition, participants passively viewed the pictures, in the other, they performed an active picture categorization task. The processing of erotic compared to romantic images was associated with a decrease in power in the alpha and lower beta band in posterior and anterior sensor clusters between 600-1,000 ms poststimulus. The finding was robust and confirmed across conditions, different quantifications, and independent from baseline activity. Furthermore, key findings regarding explicit task effects as well as ERPs sensitive to emotional arousal were replicated. Results are discussed with respect to the hypothesis that alpha- and lower beta-band activity may reflect cortical activation associated with emotional stimulus significance.
脑电图（EEG）功率分析在认知领域已经得到了广泛应用。这与情感刺激处理形成了鲜明对比，因为到目前为止，情感刺激处理的研究结果复杂且相互矛盾。为了进一步深入理解这一问题，本研究在任务变化和基线活动的背景下考察了情感刺激处理，其中包括了多项操作检查以及在不同条件下对研究结果的内部复制。参与者（N=16）观看了具有不同刺激唤醒度的色情和浪漫图片。图片的呈现时间很短（120 毫秒），并且试验间间隔被系统地改变（约 1 秒与约 8 秒）。在一种条件下，参与者被动观看图片，而在另一种条件下，他们执行主动的图片分类任务。与浪漫图片相比，色情图片的处理与刺激后 600-1000 毫秒时后头部和前头部传感器集群中 alpha 和较低 beta 频段的功率下降有关。该发现具有稳健性，并且在不同条件、不同量化以及独立于基线活动的情况下得到了确认。此外，关于明确任务效应以及对情感唤醒敏感的事件相关电位（ERP）的关键发现也得到了复制。结果讨论了关于 alpha 和较低 beta 频段活动可能反映与情感刺激意义相关的皮层激活的假设。
