Illuminating posterior targets for transcranial magnetic stimulation beyond the prefrontal cortex

Abstract

Transcranial magnetic stimulation (TMS) is rapidly developing as a therapeutic tool for multiple psychiatric disorders. All current US Food and Drug Administration-cleared TMS indications for psychiatric illness target the frontal lobes. Historically, TMS target selection was based on reports of brain lesion locations that cause illness or functional neuroimaging correlates within the prefrontal cortex. In addition to prefrontal targets, however, these neuroimaging studies have consistently implicated posterior brain regions in a variety of psychiatric disorders. Thus far, these posterior regions have rarely been tested in TMS clinical trials. In this Perspective, we consider the role in psychiatric disorders of posterior regions such as the occipital cortex, precuneus, inferior parietal lobules and cerebellum. We synthesize preliminary evidence across the few existing TMS trials targeting posterior regions and consider the risks and benefits of stimulating posterior targets for the treatment of psychiatric illness. In this Perspective, the authors review evidence suggesting that stimulating posterior regions such as the occipital cortex and cerebellum could offer new therapeutic avenues, potentially enhancing TMS efficacy across various psychiatric conditions.