The neurobiology of play: a narrative review of evidence from mice and humans for advancing neurorehabilitation.

Objective: This narrative conceptual review explores the neurobiological underpinnings of play behaviour across species, with an emphasis on how play affects brain development, social functioning, and cognitive outcomes from early life through aging. Methods: We synthesize current neuroscientific literature from animal and human studies, focusing on translational evidence involving specific brain regions (e.g., prefrontal cortex, amygdala, striatum), neurochemical systems (e.g., dopamine, opioids), and behavioral domains (e.g., executive function, emotional regulation, and social cognition). Studies are categorized by developmental stage and functional impact. Results: Evidence from rodent models demonstrates the activation of distinct neural circuits during structured and spontaneous play (e.g., hide-and-seek, rough-and-tumble), with sex-specific differences in cortical and subcortical engagement. In humans, play emerges in infancy and supports neural plasticity, language development, and executive functioning. Later in life, playfulness correlates with cognitive resilience and may act as a protective factor against neurodegeneration. The review also highlights play-based rehabilitation approaches (e.g., sensory-motor therapy, LEGO®-based interventions, sports) with demonstrated neurological and psychosocial benefits. Conclusion: Play is a multidimensional, evolutionarily conserved behaviour that engages neurobiological systems critical to development and health. Although promising evidence supports play-based interventions, further research is needed to clarify mechanisms, optimize therapeutic use, and bridge species-specific findings in translational neuroscience.