Emotion plays an important role in people’s lives. However, the neural mechanism of affective perception is still unclear. In this study, steady-state visual evoked potentials (SSVEPs) were used to explore information processing speed and interactions among cortical structures involved in affective perception. Pleasant, unpleasant, and neutral pictures selected from the International Affective Picture System were presented either in intact or phase-scrambled form at a fixed frequency, where the induced SSVEPs could be used as a frequency marker of brain activity with high temporal resolution and signal-to-noise ratio. Source estimation methods were used to reconstruct the cortical signals. The information processing of affective images was studied by phase and causal connection analysis in the cortical space to investigate the information processing speed of the local brain region and the dynamic interactions across brain regions. Experimental results showed that affective and semantic perception was accompanied by the acceleration of information processing speed in the ventral pathway. Unpleasant emotions had the fastest information processing speed in the ventral stream compared with pleasant and neutral emotions, including the middle occipital gyrus and the middle temporal gyrus, with a right hemisphere bias. In addition, unpleasant emotions were stronger than pleasant emotions in long-term causal connections in the bilateral middle temporal gyrus, and the direction was from the right hemisphere to the left hemisphere. These results provide unique insights into the cortical activities for affective perception and support the view that unpleasant emotions have priority in information perception in the middle temporal gyrus compared with pleasant and neutral emotions, with a right hemisphere bias.

情感在人们的生活中起着重要的作用。但是，情感感知的神经机制仍不清楚。在这项研究中，稳态视觉诱发电位（SSVEPs）用于探讨信息处理速度和涉及情感感知的皮质结构之间的相互作用。从国际情感图片系统中选取的愉悦，不愉快和中性的图片会以固定频率完整或相位混乱的形式呈现，其中诱导的SSVEP可以用作具有高时间分辨率和信号强度的大脑活动的频率标记噪声比。源估计方法用于重建皮层信号。通过相位和因果关系分析在皮层空间中研究了情感图像的信息处理，以研究局部大脑区域的信息处理速度以及整个大脑区域的动态交互作用。实验结果表明，情感和语义知觉伴随着腹侧途径信息处理速度的加快。与愉悦和中立的情绪（包括枕中回和颞中回，右半球偏斜）相比，不愉快的情绪在腹侧流中具有最快的信息处理速度。此外，在双侧颞中回的长期因果关系中，不愉快的情绪比愉快的情绪更强，方向是从右半球到左半球。