Emotion transitions leave a grid-like signal in brain scans
A peer-reviewed experiment detected a repeating activity pattern as adults judged changes in faces and emotional language. The finding links emotion concepts to a form of organization already studied in navigation. It comes from imaging data for 18 people, with transfer between stimulus types depending partly on how the emotional space was defined.
Science··Morning
A repeating signal during emotional judgments
A single peer-reviewed study by Yumeng Ma and Philip Kragel examined 18 adults as they compared emotional expressions and language. Imaging detected a pattern in the ventromedial prefrontal cortex, a region toward the lower middle of the frontal brain. Activity varied with the direction of changes through a space organized by pleasantness and activation. Its sixfold symmetry resembles signals investigated in research on navigation through physical and conceptual spaces.[1]
Faces and words share part of the geometry
Participants followed changing faces or sequences of words, then judged whether pleasantness or arousal had risen, fallen or stayed constant. Coordinates based on those dimensions allowed an orientation estimated from one stimulus type to transfer to the other. Results were less consistent when the researchers instead constructed the space from ratings of emotion categories: transfer appeared from language to faces, but the reverse comparison did not reproduce it.[1]
Distance signals track more consistent answers
The same brain region carried information about how far apart emotional states were. That distance signal was associated with more consistent judgments, while stronger grid-like modulation had no equivalent association with choices. Functional magnetic resonance imaging measures blood-oxygenation changes indirectly across cell populations. The small sample and particular task constrain the finding; it neither identifies individual grid cells nor establishes that this region is indispensable for organizing emotion knowledge.[1]
