Schedule of Events | Symposia

Amygdala subnuclei in processing of approaching in/outgroup others in 360 videos

Poster Session D - Monday, March 31, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Iiro Jaaskelainen¹ (iiro.jaaskelainen@aalto.fi), Gloria Mendoza Franco¹, Olli Tammilehto¹, Ville Harjunen², Niklas Ravaja², Matilde Tassinari², Inga Jasinskaja-Lahti²; ¹Aalto University, Espoo, Finland, ²University of Helsinki, Helsinki, Finland

Ample evidence from neuroimaging studies indicates that processing of various types of threats with respect to personal space involves the human amygdala. Previous fMRI studies have shown that the human amygdala is activated both in threatening situations and situations involving members perceived as belonging to a threat-outgroup, suggesting a link between threat and prejudice. However, neuroimaging studies taking multiple outgroups and amygdala subregions into account have been wanting. Here, we investigated the relationship between outgroup types and amygdala responses by using machine learning to classify fMRI responses during 360-video encounters with protagonists belonging to ingroup vs. different outgroups. In these encounters, the protagonists were initially at a distance then approached the subject finally encroaching their personal space. The classifiers were able to decode above chance level the interpersonal distance between the protagonist and the subject in the virtual space in all subregions of the amygdala, suggesting that amygdala subregions are involved in processing of interpersonal space. Notably, the classifiers were also able to distinguish outgroups above chance level using data from specific regions of the amygdala, yet only during approach of the protagonist towards the subjects. Basal subnucleus of amygdala and the situation involving an outgroup member starting to approach the perceiver were found particularly important for the successful classification. Methodologically, our results imply that it is possible to use MVPA methods to analyse amygdala subnuclei. Neuroscientifically, our result suggest that especially basal amygdala subnuclei are involved in perceiving the in/outgroup status of others who are approaching oneself.

Topic Area: EMOTION & SOCIAL: Emotional responding