Everyday experiences can evoke positive feelings that differ among individuals and guide their behavior. Although reward processing is often linked to positive feelings, the mechanisms underlying subjective positive affect and whether they are shared for varied positive experiences is unclear. Here, we used fMRI and predictive modeling to investigate how dynamic, personalized positive experiences are encoded in the brain in humans of both sexes. Neural representations and functional integration during experiences of monetary reward, social media, music, and positive autobiographical memories were used to predict participants' affect ratings of each experience. Across experiences, positive affect was encoded in multivariate neural patterns and functional coupling of distributed cortical and subcortical brain areas, including some value-linked brain regions, like orbitofrontal cortex. Restricted sets of brain representations and functional connections linked to sensory processing were involved in encoding stimulus-specific positive affect. Our findings suggest that positive affect may be computed and communicated throughout the brain. Significance Statement Different daily life experiences can evoke positive feelings that guide our behaviors. Research on mechanisms of positive feelings often assesses rewarding experiences, like winning money, yet daily positive experiences are dynamic and multifaceted. Positive feelings linked to these experiences are subjective and varied. We built computational models that use brain activation patterns and functional connections to predict participants’ positive affect ratings related to different experiences. We demonstrate that subjective positive affect is encoded in widespread patterns of neural activity and functional integration between brain regions. We show that experience-specific positive affect is sparsely encoded in activity patterns and functional connections involving sensory processing regions. Our findings show that positive feelings are encoded via complementary mechanisms throughout the brain.
Savalia et al. (Fri,) studied this question.