Vrije Universiteit Brussel, Brussel, Belgium.
Sci Rep. 2019 Feb 28;9(1):3190. doi: 10.1038/s41598-019-39859-y.
Categorizing people in groups and associating them with stereotypical behavior is an integral part of human social understanding and interaction. This study investigates where knowledge on social groups and their stereotypes is represented in the brain. We presented participants with two sentences describing a group member (e.g. the police officer) performing a behavior believed to be stereotypical of the group (e.g. makes an arrest, i.e. authoritative), and asked them to rate the degree to which the behavior was typical of the group. Our critical manipulation was the repetition of this information across the two sentences: Either both the group and the stereotype implied by the behavior was repeated, only the group was repeated, only the stereotype implied by the behavior, or neither. Results showed robust suppression of hemodynamic activation from the first to second sentence in the medial prefrontal cortex in response to the repetition of the stereotype implied in the behavior, but only when groups were different. This finding suggests that the neural representation of stereotypes is located in this area, and this is in line with similar repetition suppression research showing trait representation in this area. A suppression effect for the repetition of groups was observed in the posterior cingulate cortex, regardless of whether stereotypes were repeated or not. This finding suggests that the neural representation of groups is located in this area. Because this location is unexpected, we discuss several suggestions for future research to confirm this finding.
将人们分类到群体中，并将他们与刻板印象联系起来，是人类社会理解和互动的一个组成部分。本研究旨在探究有关社会群体及其刻板印象的知识在大脑中的何处得到体现。我们向参与者呈现了两个句子，描述了一个群体成员（例如警察）执行被认为是该群体典型行为（例如实施逮捕，即权威行为），并要求他们对该行为的典型程度进行评分。我们的关键操作是在这两个句子中重复这一信息：要么同时重复群体和行为所暗示的刻板印象，要么只重复群体，要么只重复行为所暗示的刻板印象，要么两者都不重复。结果表明，在对行为所暗示的刻板印象进行重复时，内侧前额叶皮层对从第一句话到第二句话的血液动力学激活有明显的抑制作用，但只有当群体不同时才会出现这种情况。这一发现表明，刻板印象的神经表征位于该区域，这与类似的重复抑制研究中该区域的特征表现一致。在后扣带回皮层中观察到了对群体重复的抑制效应，而不管是否重复了刻板印象。这一发现表明，群体的神经表征位于该区域。由于这个位置出乎意料，我们讨论了一些未来研究的建议，以确认这一发现。
