The infant neural mirroring system: A quarter-century in review

How humans understand others' actions is a line of critical inquiry in the psychological sciences. The neural mirroring system, which activates during both action observation and execution, has been proposed as a key mechanism underlying action understanding and related socio-cognitive functions (e.g., imitation). Examinations of the infant neural mirroring system offer valuable insights into the ontogeny of this system and its potential role in early social cognition. The 21st century has yielded the emergence and rapid expansion of research on the development of this system and its putative links to various socio-cognitive processes. However, debates within the broader neural mirroring literature question whether there is sufficient evidence supporting this system's role in social cognition. Moreover, methodological inconsistencies across studies of the infant neural mirroring system hinder a cohesive understanding of how this functions across contexts and development. The current review examines research on the infant neural mirroring system from the past quarter-century and highlights theoretical and methodological limitations of this work, as well as critical avenues for future research.