Previous studies have identified that the posterior cerebellum, which plays a role in processing temporal sequences in social events, is consistently and robustly activated when we predict future action sequences based on personality traits (Haihambo Haihambo et al. Social Cognitive and Affective Neuroscience 17(2), 241–251, 2022) and intentions (Haihambo et al. Cognitive, Affective, and Behavioral Neuroscience 23(2), 323–339, 2023). In the current study, we investigated whether these cerebellar areas are selectively activated when we predict the sequences of (inter)actions based on protagonists’ preferences. For the first time, we also compared predictions based on person-to-person interactions or single person activities. Participants were instructed to predict actions of one single or two interactive protagonists by selecting them and putting them in the correct chronological order after being informed about one of the protagonists’ preferences. These conditions were contrasted against nonsocial (involving objects) and nonsequencing (prediction without generating a sequence) control conditions. Results showed that the posterior cerebellar Crus 1, Crus 2, and lobule IX, alongside the temporoparietal junction and dorsal medial prefrontal cortex were more robustly activated when predicting sequences of behavior of two interactive protagonists, compared to one single protagonist and nonsocial objects. Sequence predictions based on one single protagonist recruited lobule IX activation in the cerebellum and more ventral areas of the medial prefrontal cortex compared to a nonsocial object. These cerebellar activations were not found when making predictions without sequences. Together, these findings suggest that cerebellar mentalizing areas are involved in social mentalizing processes which require temporal sequencing, especially when they involve social interactions, rather than behaviors of single persons.

先前的研究已经发现，当我们根据人格特征预测未来的动作序列时，在处理社会事件中的时间序列中发挥作用的后小脑会持续而稳健地激活（Haihambo Haihambo 等人，社会认知和情感神经科学 17 (2 ), 241–251, 2022) 和意图 (Haihambo et al. Cognitive, Affective, and Behavioral Neuroscience 23 (2), 323–339, 2023)。在当前的研究中，我们研究了当我们根据主角的偏好预测（交互）动作序列时，这些小脑区域是否被选择性激活。我们还首次比较了基于人与人之间的互动或单人活动的预测。参与者被要求预测一个或两个互动主角的行为，方法是在得知其中一个主角的偏好后，选择他们并将其按正确的时间顺序排列。这些条件与非社会（涉及对象）和非排序（不生成序列的预测）控制条件进行对比。结果表明，与单个主角和非社交对象相比，在预测两个互动主角的行为序列时，小脑后小腿 1、小腿 2 和小叶 IX，以及颞顶交界处和背侧内侧前额叶皮层被更强烈地激活。与非社会对象相比，基于单个主角在小脑和内侧前额叶皮层的更腹侧区域招募的 IX 小叶激活的序列预测。在没有序列的情况下进行预测时，没有发现这些小脑激活。总之，这些发现表明，小脑心智化区域参与了需要时间排序的社会心智化过程，特别是当它们涉及社会互动而不是单个人的行为时。