Imitation is ubiquitous in newborns and socially naïve individuals, yet its initial driving mechanism remains unclear. Mainstream theories attribute imitation to social reward, but this account struggles to explain why infants without social concepts or socially isolated animals imitate. Here I propose an alternative hypothesis: the initial impetus for imitation is goal-setting driven by D1 dopamine pathways—observing another’s action is directly encoded by the dopamine system as a goal worth pursuing, thereby initiating the behavior. Social approval serves as a secondary reinforcer via D2/D3 pathways, consolidating imitation into social learning, but it is not the initial trigger. This hypothesis integrates evidence from dopamine functional specialization, neonatal imitation, the null finding of D2/D3 blockade on facial mimicry (Korb et al., 2023), and imitation deficits in Parkinson’s disease, and yields testable experimental predictions. This paper attempts to reposition imitation as a fundamental mechanism of behavioral motivation rather than a byproduct of social cognition.
Hui Xiang (Sun,) studied this question.