Neural signature of mood

The distributed pattern of activity — spectral, spatial and network — that correlates with spontaneous fluctuations of mood over hours to days. Studies using chronically implanted electrodes have shown that naturalistic mood variation is encoded in limbic activity, for instance in beta- or gamma-band coherence between structures such as the amygdala, hippocampus and orbitofrontal/cingulate cortex.

The most consistent finding is that the signature is highly individual: the informative frequency band, the informative site, and even the sign of the relationship differ across people. This individuality is precisely why psychiatric neuromodulation has shifted toward per-patient biomarker discovery rather than searching for one universal mood signal — a shift that trades population generality for within-patient reliability.