Modelling the Neurobiology of ADHD Using Human iPSC Systems: A Multimodal Platform for Mechanistic Discovery.

Attention deficit hyperactivity disorder (ADHD) is a common and highly heterogeneous neurodevelopmental condition with complex biological underpinnings. Despite substantial progress in identifying genetic and neurobiological correlates, the cellular mechanisms linking genetic variation to functional brain alterations remain poorly understood. Human induced pluripotent stem cell (iPSC) technology provides a powerful platform to investigate these mechanisms by enabling the generation of patient-specific neural cell types and the direct interrogation of molecular, cellular, and network-level phenotypes. In this review, we summarise the current understanding of the neurobiological mechanisms underlying ADHD, including dopaminergic dysregulation, delayed neurodevelopmental maturation, and excitatory/inhibitory imbalance. We then discuss how iPSC-based models, combined with genome engineering and advanced functional assays, can be used to dissect gene-specific effects, study neural circuit development, and establish scalable platforms for therapeutic discovery. Finally, we outline key methodological considerations for designing robust iPSC-based models of ADHD. Together, these approaches provide new opportunities to bridge genetic risk with cellular function and accelerate the development of mechanistically informed therapeutic strategies.