When 2 people tap together, they adjust their timing to their partner. We investigated whether having an adaptive partner leads to better pitch perception and cognition (measured by electrophysiological mismatch negativity [MMN] and N400 responses to pitch change) compared with having a nonadaptive partner. In the nonadaptive condition, people tapped along to 3 tones generated by the computer at a fixed 800 ms interonset interval (IOI). In the adaptive condition, the computer continuously adjusted the IOI of the tones in response to the taps of the subject. Twenty percent of the time, the fourth tone was changed in pitch by 1/48th octave. Results showed that both MMN and N400 were enhanced in response to deviant targets with the adaptive compared to nonadaptive partner, suggesting that having an adaptive partner enables better perception and cognitive processing of the contents of a sound sequence.