preprint

Processing affectively charged visual stimuli typically results in increased amplitude of specific event-related potential (ERP) components. Low-level features similarly modulate electrophysiological responses, with amplitude changes proportional to variations in stimulus size and contrast. However, it remains unclear whether emotion-related amplifications during visual word processing are necessarily intertwined with changes in specific low-level features or, instead, may act independently.
In this pre-registered electrophysiological study, we varied font size and contrast of neutral and negative words while participants were monitoring their semantic content. We examined ERP responses associated with early sensory and attentional processes as well as later stages of stimulus processing. Results showed amplitude modulations by low-level visual features early on following stimulus onset – i.e., P1 and N1 components –, while the LPP was independently modulated by these visual features. Independent effects of size and emotion were observed only at the level of the EPN. Here, larger EPN amplitudes for negative were observed only for small high contrast and large low contrast words. These results suggest that early increase in sensory processing at the EPN level for negative words is not automatic, but bound to specific combinations of low-level features, occurring presumably via attentional control processes.

处理情感负荷的视觉刺激通常会导致特定事件相关电位（ERP）成分的幅度增加。低级特征同样调节电生理反应，其幅度变化与刺激大小和对比度的变化成比例。然而，在视觉词汇处理过程中，情绪相关的放大作用是否必然与特定低级特征的变化交织在一起，或者，这些作用可能独立发生，尚不明确。在本项已注册的电生理学研究中，我们在参与者监控语义内容的同时，改变了中性词和负面词的字体大小和对比度。我们考察了与早期感觉和注意力过程以及刺激处理后期阶段相关的ERP反应。结果显示，在刺激出现后早期，低级视觉特征的幅度调节作用即P1和N1成分，而晚期的LPP则独立地受到这些视觉特征的调节。仅在EPN层面观察到大小和情绪的独立效应。在此，仅对小型高对比度和大型低对比度的负面词观察到较大的EPN幅度。这些结果表明，在EPN层面针对负面词的早期感觉处理增加并非自动发生，而是与特定低级特征的组合密切相关，这可能是通过注意力控制过程实现的。