Applications and potential mechanisms of transcranial magnetic stimulation in autism spectrum disorders

Transcranial magnetic stimulation (TMS) is a non-invasive neuromodulation technique widely applied in clinical interventions for various neurological disorders. Its safety profile, ease of operation, and potential therapeutic value have prompted exploration in autism spectrum disorder (ASD). However, TMS efficacy in ASD exhibits marked heterogeneity, primarily due to the lack of robust scientific theoretical support for existing therapeutic approaches—this severely hinders the standardisation of TMS in ASD clinical practice and the improvement of therapeutic outcomes. The present narrative review first provides an in-depth synthesis of existing TMS research in ASD, focusing on the safety validation of different stimulation protocols, the scientific rationale for protocol selection, and the observed differences in efficacy across recent studies. It also explores the suitability of stimulation coil types and the rationality of target localisation, offering practical guidance for harnessing TMS’s therapeutic potential. Building on this, the core of the review focuses on summarising both potential and proposed mechanisms of TMS in ASD, encompassing key dimensions such as ion channels, excitatory-inhibitory imbalance, synaptic plasticity, neural oscillations, neuroinflammation, and the gut microbiome, while elucidating the interrelationships among these factors. This narrative review systematically synthesises the proposed mechanisms by which TMS may affect ASD, aiming to provide a foundation for optimising TMS-based therapeutic regimens for ASD and advancing the development of TMS as a more effective and reliable treatment option.