Musical reward prediction errors engage the nucleus accumbens and motivate learning

Abstract

Enjoying music reliably ranks among life’s greatest pleasures. Like many hedonic experiences, it engages several reward-related brain areas, with activity in the nucleus accumbens (NAc) most consistently reflecting the listener’s subjective response. Converging evidence suggests that this activity arises from musical “reward prediction errors” (RPEs) that signal the difference between expected and perceived musical events, but this hypothesis has not been directly tested. In the present fMRI experiment, we assessed whether music could elicit formally modeled RPEs in the NAc by applying a well-established decision-making protocol designed and validated for studying RPEs. In the scanner, participants chose between arbitrary cues that probabilistically led to dissonant or consonant music, and learned to make choices associated with the consonance, which they preferred. We modeled regressors of trial-by-trial RPEs, finding that NAc activity tracked musically elicited RPEs, to an extent that explained variance in the individual learning rates. These results demonstrate that music can act as a reward, driving learning and eliciting RPEs in the NAc, a hub of reward- and music enjoyment-related activity.

Musical anhedonia and rewards of music listening: current advances and a proposed model

“…In the domain of music, Gold et al . showed that musical stimuli, specifically chords and chord progressions with consonant or dissonant endings, can generate rewards and reward prediction errors that motivate learning in a reinforcement‐learning protocol . This result shows that because of the systematic relationship between consonance and pleasure at least in most westernized listeners, music itself—specifically, consonant chord endings to chord progressions—can function both as a prediction (in this case, the chord progression) and a reward (in this case, consonant endings as opposed to dissonant endings).…”

“…While this work indicates that pleasurable music engages similar brain structures to other rewarding experiences, more recent work has investigated the idea that music itself can serve as a reward. One recent fMRI study investigated the neural responses to music in a reward‐learning context . Taking an established reward prediction error task and substituting music (where consonant music is assumed as a reward, and dissonant music is punishment), the authors identified that the NAcc responded to reward prediction errors in music.…”

“…One recent fMRI study investigated the neural responses to music in a reward-learning context. 34 Taking an established reward prediction error task and substituting music (where consonant music is assumed as a reward, and dissonant music is punishment), the authors identified that the NAcc responded to reward prediction errors in music. Interestingly, this suggests that the NAcc responds similarly to musical reward as to other pleasurable experiences, such as a monetary reward.…”

Behavioral, physiological, and neural signatures of surprise during naturalistic sports viewing

“…Reward signals are intimately linked with the activity of dopamine neurons in regions of the brainstem such as the ventral tegmental area (VTA), as well as targets of those neurons, particularly the nucleus accumbens (NAcc). Classically, the VTA 43,44 and NAcc 12,45,46 respond strongly when rewards are larger or earlier than expected (i.e., reward prediction errors, or RPEs). However, the VTA can respond more broadly to variables other than reward 47 , including sensory PEs 48-50 , unexpected events 51,52 , aversive PEs 53 , changes in hidden belief states 31,54 , reward expectation 55,56 , advance information 57 , and stimulusstimulus learning 58 , all in the absence of (or controlling for) reward.…”

“…Surprise is theorized to be critical for learning and memory 6,7 , updating our beliefs about the structure of the world 8 , and demarcating events in the continuous flow of time 9 . Moreover, although people typically prefer certainty about outcomes that are instrumental for survival 10 , in domains with noninstrumental information, such as narratives, music, and sports, people tend to prefer violations of their expectations [11][12][13] , suggesting that surprise is often a rewarding affective experience.…”