Somatosensory processing and body representation

Recent years have seen increasing numbers of transcranial magnetic stimulation (TMS) studies focusing on somatosensory processing. Most have centered on the primary somatosensory functions of tactile detection, localization and discrimination, and have applied TMS to primary somatosensory areas. These studies confirm the basic functions of primary somatosensory areas, and the behavioural and physiological effects of different TMS protocols. Fewer studies, however, have investigated higher somatosensory function. Here, we review the somatosensory TMS literature both in and beyond primary somatosensory areas. We discuss the plausibility of modulating multisensory representations of one's own body via TMS, and highlight the potential for TMS to probe higher cognitive functions through the modulation of unimodal perceptual systems such as touch, vision or proprioception. (C) 2009 Elsevier Srl. All rights reserved.