AI Insight
Researchers discovered that the human ventromedial prefrontal cortex (vmPFC) organizes emotion concepts using a grid-like coordinate system, similar to how the brain maps physical space. Using fMRI scanning while participants viewed facial expressions and emotional phrases, the team found hexadirectional patterns characteristic of grid cell coding that represented emotions along dimensions of valence and arousal. This grid-like representation worked across different types of stimuli and was independent of behavior, suggesting the brain uses an abstract coordinate system to organize emotion knowledge.
Why it matters
This finding reveals a fundamental organizing principle for how the brain represents abstract emotional concepts, which could improve understanding of emotional processing disorders and inform treatments for conditions involving emotional dysregulation. The discovery that emotions are mapped similarly to physical space suggests the brain may use common computational principles for navigating both concrete and abstract conceptual spaces.
by Yumeng Ma, Philip A. Kragel
Human emotional experiences vary widely in everyday life, yet they are systematically organized within a continuous affective space defined by valence and arousal. Although this circumplex organization has shaped decades of research, its neural implementation remains unclear. Here, we asked whether abstract emotion concepts are encoded using grid-like coordinate principles in the human brain. During fMRI, participants tracked trajectories through affective space conveyed through morphs of facial expressions and sequences of phrases. We found that ventromedial prefrontal cortex (vmPFC) encoded affective space with robust hexadirectional modulation characteristic of grid-like coding. This coordinate representation generalized across stimulus modalities, indicating abstraction beyond perceptual features. The grid-like signal reflected a metric organization of emotion concepts independent of overt behavior, whereas distance-related signals in vmPFC predicted trial-by-trial affective judgements. Together, these findings suggest that emotion knowledge is structured by a grid-like coordinate system in the human brain that can support predictive inference and flexible decision-making.