Objective: Joint agency–the experience of controlling action outcomes together with another person–is a core construct in social cognition. We reanalyzed the open Joint Agency EEG dataset (N = 23 for condition contrast; N = 21 for rating split) to test whether intra-brain alpha-band (8–13 Hz) connectivity supports this experience.

Method: Specifically, we estimated seed-based imaginary coherence from frontal electrode Fz_L to distributed scalp channels. Building on prior work linking auditory ERPs and inter-brain beta synchrony to joint agency, we tested two contrasts: (1) objective task condition (musical duet/joint vs constant-pitch/individual) and (2) subjective experience (within-subject median split of JointAgencyRatings: high vs low). Subject-level maps were compared using cluster-based one-sample permutation tests with channel-adjacency correction.

Results: In both analyses, no clusters survived correction (p < .05). Although descriptive topographies showed spatially structured variation, effects were not statistically reliable at the cluster level.

Discussions: These null results provide informative constraints on alpha-gating accounts of joint agency. Practically, they suggest that future studies should test alternative mechanisms, time windows, and network targets when probing neural signatures of shared agency.