The Extrastriate Body Area and identity processing: An fMRI guided TMS study

The extrastriate body area (EBA) is a body-selective focal region located in the lateral occipito-temporal cortex that responds strongly to images of human bodies and body parts in comparison with other classes of stimuli. Whether EBA contributes also to the body recognition of self versus others remains in debate. We investigated whether EBA contributes to self-other distinction and whether there might be a hemispheric-side specificity to that contribution using double-pulse transcranial magnetic stimulation (TMS) in right-handed participants. Prior to the TMS experiment, all participants underwent an fMRI localizer task to determine individual EBA location. TMS was then applied over either right EBA, left EBA or vertex, while participants performed an identification task in which images of self or others' right, or left hands were presented. TMS over both EBAs slowed responses, with no identity-specific effect. However, TMS applied over right EBA induced significantly more errors on other's hands than noTMS, TMS over left EBA or over the Vertex, when applied at 100-110 ms after image onset. The last three conditions did not differ, nor was there any difference for self-hands. These findings suggest that EBA participates in self/other discrimination.