Psychological Sciences Research Institute (IPSY), Institute of Neuroscience (IoNS), University of Louvain, 1348 Louvain-la-Neuve, Belgium.
Soc Cogn Affect Neurosci. 2018 Jan 1;13(1):72-79. doi: 10.1093/scan/nsx135.
The frequency-tagging approach has generally been confined to study low-level sensory processes and always found related activation over the occipital region. Here for the first time, we investigated with it, high-level socio-cognitive functions, i.e. the processing of what other people are looking at which is referred to as level 1 visual perspective taking (VPT). Sixteen participants were presented with visual scenes alternating at 2.5 Hz which were depicting a person and an object in a room, while recording electrophysiological brain activity. The person orientation and object position changed at every stimulus but the person in the room always faced the object, except on every fifth stimulus. We found responses in the electroencephalography (EEG) spectrum exactly at the frequency corresponding to the presentation of the scenes where the person could not see the object, i.e. 0.5 Hz. While the 2.5 Hz stimulation rate response focused on typical medial occipital sites, the specific 0.5 Hz response was found mainly over a centro-parietal region. Besides a robust group effect, these responses were significant and quantifiable for most individual participants. Overall, these observations reveal a clear measure of level 1-VPT representation, highlighting the potential of EEG frequency-tagging to capture high-level socio-cognitive functions in the brain.
频率标记方法通常局限于研究低水平的感觉过程，并且总是在枕叶区域发现相关的激活。在这里，我们首次用它研究了高水平的社会认知功能，即对他人正在看什么的处理，这被称为一级视觉透视（VPT）。16 名参与者被呈现以 2.5 Hz 交替的视觉场景，这些场景描绘了一个人和一个物体在一个房间里，同时记录脑电图（EEG）脑电活动。人的方向和物体的位置在每个刺激物之间变化，但房间里的人总是面对物体，除了每第五个刺激物。我们在脑电图（EEG）频谱中发现了与场景呈现完全对应的响应，即 0.5 Hz，而人不能看到物体。当 2.5 Hz 刺激率反应集中在典型的内侧枕叶部位时，特定的 0.5 Hz 反应主要在中央顶叶区域。除了强大的群体效应外，这些反应在大多数个体参与者中都是显著和可量化的。总的来说，这些观察结果揭示了一级-VPT 表示的明确衡量标准，突出了 EEG 频率标记在大脑中捕捉高水平社会认知功能的潜力。
