Schedule of Events | Symposia

Whole brain decoding of common and type-specific positive affect

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

Tejas Savalia¹ (tejas.savalia@emory.edu), Sophia Martin¹, Sagarika Devarayapuram Ramakrishna¹, Alexandra Cohen¹; ¹Emory University

Experimental research often uses distinct types of reinforcers interchangeably. However, different reinforcers engage different brain systems and may evoke varying levels of affect. Recent findings show that negative affective experiences are encoded via both modality specific and modality general representations in the brain (Ceko et al. (2022)). It is not known whether positive affective experiences are represented in the same way. In a fMRI scanner, 53 adult participants aged 18-25 experienced 4 types of positive affective stimuli: monetary rewards, social media clips, short music clips, and positive autobiographical memories. After each experience participants rated how much they wanted to experience the same situation again. Interestingly, winning money, and recalling past positive memories were rated as more positive experiences than participant preferred short social media clips and music. We then use predictive modeling with five-fold cross validation to assess multivariate whole-brain patterns which encode participants’ subjective experiences. Classification models successfully decode each stimulus type, though not intensity levels. We then used a whole brain partial least squares (PLS) regression model to jointly predict subjective ratings of each stimulus type and for a common affective system including all subjective ratings. PLS regression indicates a reliable stimulus type-specific systems which predict subjective ratings but provides mixed evidence for a common system – music and video experience ratings were predicted better than ratings for pleasant autobiographical memories and winning money. Preliminary analyses suggest that positive affective experiences may be distinctively encoded depending on stimulus modality.

Topic Area: EMOTION & SOCIAL: Emotional responding