Listening to a Consonant Chord Progression during Live Face-to-Face Gaze Enhances Neural Activity in Social Systems.

Although music has been associated with increased prosocial behavior, the underlying mechanisms for music-facilitated social benefits are not known. We test the hypothesis that chord progressions promote social bonding between dyads by shared temporal alignment of frequency spectra. Two musical conditions were presented to 20 pairs of participants (equal numbers of males and females), one with either a structured chord or predictable progression and the other with an unstructured and unpredictable composition of the same notes. Functional near-infrared spectroscopy signals were recorded simultaneously from both partners during the music conditions with and without gazing at a live partner's face. The right angular gyrus, right somatosensory association cortex, and bilateral dorsal lateral prefrontal cortex increased activation during live face gaze combined with the structured chord progression condition. Further, subjective ratings of subjective connectedness were associated with both activity in the right superior and middle temporal gyri during face gaze and the right angular gyrus during chord progressions. These findings link live face-to-face gaze while listening to structured chord progressions to neural systems that are responsive to predictive alignment of co-occurring acoustic spectra and perceptions of social connectedness.