TMS-EEG responses across the lifespan: Measurement, methods for characterisation and identified responses

The combination of transcranial magnetic stimulation (TMS) and electroencephalography (EEG) allows probing of the neurophysiology of any neocortical brain area in vivo with millisecond accuracy. TMS-EEG is particularly unique compared with other available neurophysiological methods, as it can measure the state and dynamics of excitatory and inhibitory systems separately. Because of these capabilities, TMS-EEG responses are sensitive to the brain state, and the responses are influenced by brain maturation and ageing, making TMS-EEG a suitable method to study age-specific pathophysiology. In this review, we outline the TMS-EEG measurement procedure, the existing methods used for characterising TMS-EEG responses and the challenges associated with identifying the responses. We also summarise the findings thus far on how TMS-EEG responses change across the lifespan and the TMS-EEG features that separate typical and atypical brain maturation and ageing. Finally, we give an overview of the gaps in current knowledge to provide directions for future studies.

Automated summary

The combination of transcranial magnetic stimulation (TMS) and electroencephalography (EEG) allows for accurate measurement of neurophysiology in vivo, specifically in the neocortical brain area, with the ability to measure excitatory and inhibitory systems separately. Due to its sensitivity to brain state and influences of brain maturation and ageing, TMS-EEG is a suitable method to study age-specific pathophysiology. This review outlines the measurement procedure, existing methods, challenges, and findings of TMS-EEG, as well as provides directions for future studies.