Our findings show that interpersonally coordinated actions are preceded and accompanied by between-brain oscillatory couplings," says Ulman Lindenberger. The results don't show whether this coupling occurs in response to the beat of the metronome and music, and as a result of watching each others' movements and listening to each others' music, or whether the brain synchronization takes place first and causes the coordinated performance. Although individual's brains have been observed getting tuning into music before, this is the first time musicians have been measured jointly in concert.