Two is company: The posterior cerebellum and sequencing for pairs versus individuals during social preference prediction

Abstract

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.

Exciting the social butterfly: Anodal cerebellar transcranial direct current stimulation modulates neural activation during predictive social mentalizing

“…Neurological studies have found that cerebellar Crus 1 and 2 were preferentially recruited when we have to memorize sequences of higher-order traits ( Pu et al, 2020 ), beliefs ( Heleven et al, 2019 ; Ma et al, 2021 ) and goal-directed social navigation ( Li et al, 2021 , 2024 ) in comparison to conditions that did not explicitly require sequencing or involved non-social events (cf. meta-analysis by Van Overwalle et al (2020) Importantly, Crus 1, 2 and lobule IX were also preferentially recruited when making predictions about upcoming actions based on known traits ( Haihambo et al, 2022 ), intentions ( Haihambo et al, 2023 ) and preferences of others ( Haihambo et al, 2023 ) in comparison with non-sequential and non-social conditions. Together these studies suggest that the posterior cerebellum plays a key role in sequencing, mentalizing and future oriented thinking.…”