Transcranial magnetic stimulation: applications in basic neuroscience and neuropsychopharmacology

Introduced 15 years ago, transcranial magnetic stimulation (TMS) is a non-i nvasive means of stimulating the cortex that has proved to be a unique tool for probing brain-behaviour relationships. While a therapeutic role for TM S in neuropsychiatry is uncertain, the utility of TMS in studying brain fun ction has been demonstrated in diverse neuroscience applications. We review studies in animals on the mechanisms of action of TMS, and present a summa ry of the applications of TMS in basic neuroscience. TMS is still a relativ ely young technique, and unanswered questions remain regarding its acute an d chronic impact on neural excitability and various aspects of brain functi on. Nonetheless, recent work with TMS has demonstrated its unique role in c omplementing other tools for studying brain function. As a brain interventi on tool, TMS holds the promise of moving beyond correlative studies to help define the functional role of cortical regions in selected cognitive and a ffective processes.